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The Candelaria iron oxide-copper-gold deposit in Chile was formed by superimposed, episodic hydrothermal pulses with contrasting composition and temperature, according to micro-textural and compositional variations in actinolite, a common alteration mineral.

GlvA, a 6-phospho-alpha-glucosidase from Bacillus subtilis assigned to glycoside hydrolase family 4, catalyzes the hydrolysis of maltose 6'-phosphate via a redox-elimination-addition mechanism requiring NAD+ as cofactor. In contrast to previous reports and consistent with the proposed mechanism, GlvA is only activated in the presence of the nicotinamide cofactor in its oxidized, and not the reduced NADH, form. Significantly, GlvA catalyzes the hydrolysis of both 6-phospho-alpha- and 6-phospho-beta-glucosides containing activated leaving groups such as p-nitrophenol and does so with retention and inversion, respectively, of anomeric configuration. Mechanistic details of the individual bond cleaving and forming steps were probed using a series of 6-phospho-alpha- and 6-phospho-beta-glucosides. Primary deuterium kinetic isotope effects (KIEs) were measured for both classes of substrates in which either the C2 or the C3 protons have been substituted with a deuterium, consistent with C-H bond cleavage at each center being partially rate-limiting. Kinetic parameters were also determined for 1-[2H]-substituted substrates, and depending on the substrates and the reaction conditions, the measurements of kcat and kcat/KM produced either no KIEs or inverse KIEs. In conjunction with results of Brønsted analyses with both aryl 6-phospho-alpha- and beta-glucosides, the kinetic data suggest that GlvA utilizes an E1cb mechanism analogous to that proposed for the Thermotoga maritima BglT, a 6-phospho-beta-glucosidase in glycoside hydrolase family 4 (Yip, V.L.Y et al. (2006) Biochemistry 45, 571-580). The pattern of isotope effects measured and the observation of very similar kcat values for all substrates, including unactivated and natural substrates, indicate that the oxidation and deprotonation steps are rate-limiting steps in essentially all cases. This mechanism permits the cleavage of both alpha- and beta-glycosides within the same active site motif and, for activated substrates that do not require acid catalysis for cleavage, within the same active site, yielding the product sugar-6-phosphate in the same anomeric form in the two cases.

The Dublin Gulch intrusion is a member of the Tombstone plutonic suite, a linear belt of middle Cretaceous intrusions that extend across the Yukon Territory. Like many of the intrusions in this suite, the Dublin Gulch intrusion is associated with several different zones of gold and tungsten mineralization, within and immediately adjacent to the intrusion. The Eagle zone (50.3 Mt @ 0.93 g/t gold), located in the southwestern part of the Dublin Gulch intrusion, hosts the most significant concentration of gold in the area. The gold occurs in a broadly east–west-striking, steeply south-dipping series of sheeted veins. The veins consist of early quartz–scheelite±pyrrhotite±pyrite±arsenopyrite, and are associated with K-feldspar±albite alteration envelopes. These grade out to and are overprinted by sericite–carbonate±chlorite alteration. The same assemblage also occurs in veinlets that refracture sheeted quartz veins and contain the majority of the gold. The gold occurs with molybdenite, lead–bismuth±antimony sulfosalts, galena, and bismuthinite. Gold correlates strongly with bismuth (r 2=0.9), a relationship common to several intrusion-related gold deposits, but has a poor correlation with all other elements. Tungsten and molybdenum have a weak inter-element correlation (r 2=0.55) and paragenetically pre-date the majority of gold precipitation. Lead, zinc, copper, silver, antimony, and arsenic have moderate to strong inter-element correlations (0.58 to 0.93). The change from tungsten-bearing mineralization through to gold–bismuth-rich ores with elevated syn- to post-ore lead, zinc, copper, silver, antimony, and arsenic can be grossly correlated with a change in hydrothermal fluid composition. Early scheelite-bearing quartz contains primary CO2-rich fluid inclusions, which are post-dated by secondary inclusions with higher salinities (up to 15 wt% NaCl equiv.) and less CO2. These latter inclusions are interpreted to coincide with the later gold–bismuth and base metal mineralization. The favored genetic model is one in which early CO2-rich fluids exsolved from a magma with an initially high CO2 content, but progressively became more saline and H2O-rich as the system evolved.

The Limonite Creek property in north-central British Columbia contains several zones of silicic and acid-sulphate alteration. These zones grade through advanced argillic and aluminous mineral assemblages to sericitic and regional propylitic alteration. Alteration assemblages are characteristic of high-sulphidation systems, although the abundance of pyrophyllite and andalusite suggests formation at depths below typical epithermal environments. Alteration occurred between 212 and 52 Ma as determined from field relations and U-Pb dating of intrusions. The deformed nature of the alteration assemblages and a minimum age of alunite (144 ± 8 Ma) suggest formation in latest Triassic to Middle Jurassic time. Based on these age constraints, alteration zones at Limonite Creek are significantly older than the Eocene Equity Silver deposit (ca. 60 Ma), despite the latter's proximity and similar styles of alteration. Based on the new dates, host rocks at Limonite Creek are Late Triassic or older, and hence regional stratigraphy needs reassessment. Extensive exotic limonite deposits occur around the alteration zones and at lower elevations to the south. Radiocarbon dating indicates that the deposits have been accumulating for at least 8000 years. Iron released during weathering was transported in low-pH waters and precipitated initially as ferrihydrite, with subsequent conversion to goethite. Water chemistry confirms that the process is still active. In addition to iron, the limonite contains minor copper and zinc. The formation of low-pH waters and the transport of iron resulted from weathering of pyrite-rich alteration assemblages with negligible buffering capacity.

The Liese zone is a recently discovered high-grade gold deposit on the Pogo claims, approximately 90 miles (145 km) southeast of Fairbanks. A conservative geologic resource for the Liese zone is 9.98 million tons at an average grade of 0.52 oz/t, for a total of 5.2 million contained ounces. The region is underlain by highly deformed, amphibolite-grade paragneiss and minor orthogneiss of the Late Proterozoic(?) to middle Paleozoic Yukon-Tanana terrane, which has been intruded by Cretaceous felsic granitoid bodies thought to be related to gold mineralization in the Fairbanks area and elsewhere along the Tintina gold belt. The Liese zone is hosted primarily in gneiss, and lies approximately 1.5 km south of the southern margin of the Late Cretaceous Goodpaster batholith. Mineralization occurs in three or more tabular, gently dipping quartz bodies, designated L1 (uppermost), L2, and L3 (lowermost). The thickness of the quartz bodies ranges from 1 to 20 m, averaging approximately 7 m. The quartz contains approximately 3 percent ore minerals, including pyrite, pyrrhotite, loellingite, arsenopyrite, chalcopyrite, bismuthinite, various Ag-Pb-Bi ± S minerals, maldonite, native bismuth, and native gold. Early biotite and later quartz-sericite-stockwork and sericite-dolomite alteration are spatially associated with the Liese zone, which shows characteristics of both vein and replacement styles of mineralization. Geochemical data indicate a strong correlation between gold and bismuth, and weaker correlations between gold, silver, and arsenic. Based on U-Pb dating of intrusive rocks, the Liese zone was formed between 107 and 94.5 m.y. ago, although 40Ar/39Ar cooling ages on alteration minerals return younger ages of 91 Ma, suggesting a protracted or multiphase thermal history. The Liese zone may represent a deep-seated manifestation of the "intrusion-related" gold deposit type.

An under-recognized and economically important class of intrusion-related gold deposits, which occur within magmatic provinces best known for tungsten and/or tin mineralization, is described with reference to seven major deposits (Fort Knox, Mokrsko, Salave, Vasilkovskoe, Timbarra, Kidston and Kori Kollo). These gold deposits contain a metal suite that includes some combination of bismuth, tungsten, arsenic, tin, molybdenum, tellurium and antimony, and contrasts with that found in the more widely-developed gold-rich porphyry copper and related deposits. The gold deposits associated with tungsten and/or tin provinces are located in cratonic margins, in a landward or back-arc position relative to continental margin arcs (where recognized), or within continental collisional settings. The deposits are related genetically to felsic domes, stocks or plutons of intermediate oxidation state, both magnetite- and ilmenite-series magmas are represented. The intrusion-hosted gold deposits are most commonly of sheeted vein/veinlet type, although greisen-like, disseminated and breccia deposits are also described. Gold may also be concentrated more distally (1–3 km) with respect to the intrusions, where deposits may be of skarn, disseminated replacement or vein types. K-feldspar, albite and/or sericitic alteration assemblages, commonly including carbonate, accompany the gold mineralization. In sheeted vein deposits, alteration is normally restricted to narrow envelopes around veins, whereas more pervasive alteration occurs in greisen-like, disseminated and shallow ( 100 tonnes (3 million oz) of gold, thereby highlighting the gold potential of intrusion-related deposits beyond the more traditionally explored gold and copper provinces in arc terranes.

Zones of advanced argillic alteration constituting lithocaps are commonplace in the shallow parts of porphyry copper systems. Similar lithocaps are also recognized in the shallowly eroded southern part of the Bolivian tin-silver belt, where mineralization typically is centred on felsic volcanic domes. A well-preserved lithocap at Potosi is dominated by vuggy residual quartz and contained the world's largest silver resource, whereas the basal remnant of a lithocap at Pulacayo is composed of barren quartz-alunite. Minor gold occurs in the structurally controlled roots of a lithocap at Tasna. The mineralization in these lithocaps is of high-sulphidation type and was generated in the epithermal environment. In contrast, the tin- and base metal-bearing massive sulphide veins and associated sericitic and quartz-tourmaline alteration that underlie the Bolivian lithocaps are typified by sulphides of low sulphidation state, but are dominantly mesothermal rather than epithermal in character. Magma chemistry is believed to account for the characterization of Bolivian lithocaps by silver-tin-antimony and porphyry copper lithocaps by gold-copper-arsenic. Low-grade, bulk-tonnage silver mineralization within Bolivian lithocaps and high-grade tin-bearing veins concealed beneath them both constitute attractive exploration objectives.

The Literary Evidence for the use of fetters in the ancient world, both for prisoners of war and slaves, is fairly plentiful and has recently been examined by the writer in preparation for a study of the archaeological evidence for slavery in the ancient world (Thompson 1993). Three well-attested cases of the dedication of fetters in Greek history which have been noticed in passing by translators and commentators (e.g. Rouse 1902, 233), but which have not received in total the attention they deserve, are of particular interest.

To study the effect of endophyte (Acremonium coenophialum) on hypothalamic and striatal dopamine D2 receptors, male rats (n = 14/group) were pair-fed diets containing 50% Rat Chow and 50% either endophyte-infected (E+) or noninfected (E-) fescue (Festuca arundinacea Schreb.) seed for 21 days. Concentrations of ergovaline and saturated pyrrolizidines were 1.91 micrograms/g and 2.84 mg/g, respectively in E+, and undetectable in E- fescue seed. To monitor endophyte effects, rats were weighed weekly and serum derived from trunk blood (d 21) was analyzed for prolactin. Corpus striatum and hypothalamic tissue was assayed for dopamine D2 receptors using [3H]spiperone and [125I]epidepride, respectively. The endophyte depressed (P.06) serum prolactin concentrations. Average daily gain during the study (21 d) was depressed (P.0043) in rats fed E+ compared to controls. The endophyte increased (P.03) striatal D2 receptor affinity (KD = 48.70 vs 54.95 pM) with no change (P.28) in receptor density (Bmax = 25.59 vs 28.00 pmol/mg of tissue) in E+ and E- rats, respectively. Hypothalamic D2 receptor density (Bmax = 1.79 vs 1.57 pmol/mg of tissue) and affinity (KD = 17.5 vs 17.26 pM) were not (P.66) different between E+ and E- rats, respectively. These data suggest changes in D2 receptor binding characteristics, particularly receptor affinity, may contribute to signs of fescue toxicosis.

The Archaeological Journal, 111, 106-128

The O'Toole orebody is the first significant nickel sulfide deposit of the volcanic peridotitc association to be found in Brazil. It is in the Archean Morro do Ferro greenstone belt in the southwest part of Minas Gerais, Brazil. The deposit is hosted by the Morro do Niquel unit characterized by a komatiitic suite of rocks, with low CaO/Al 2 O 3 ratios ( approximately 1) and a high Al 2 O/TiO 2 ( approximately 20), including olivine peridotite, peridotite, pyroxenite, and basalt flows. Komatiitic lava flows are massive or layered with spinifex tops and basal olivine cumulates. Pillowed lava flows and breccias occur subordinately intercalated with chemical precipitates and tuffs that form a minor part of the unit. The Morro do Niquel assemblage has undergone at least three major deformational events accompanied by fold development resulting in a dominant north-west subvertical structural trend. The rocks have undergone upper greenschist to lower amphibolite metamorphism with postulated peak temperatures of 550 degrees C and pressures of 3 kbars or more.Four cycles of southwest-facing serpentinite-clinopyroxenite-amphibolite separated by banded iron-formation have been defined to date in the O'Toole sequence. The deposit is associated with the upper cycle that is 60 m thick and has been divided into five main units: ore horizon (4 m), serpentinite (13 m), clinopyroxenite (15 m), amphibolite (20 m), and banded iron-formation (16 m). The orebody is tabular, subvertical, and contains five interconnected shoots over a strike distance of 1,600 m and downdip extension of 500 m. The ore horizon occurs at the base of massive serpentinite with an iron-formation footwall. Five ore types are defined: breccia, matrix, disseminated, stringer, and banded ores. The ore mineral assemblage is pyrrhotite-pentlandite-chalcopyrite with significant cobaltite and platinum-group minerals (PGM). Secondary minerals occur in the oxidized cap.The ore appears to have formed in an embayment characterized by the thinning of the footwall sediments beneath the O'Toole deposit. This embayment is postulated to be primary and may have provided the trap for the accumulation of the immiscible sulfide droplets carried by the ultramaric flow host. The matrix and disseminated sulfides represent a primary distribution in the embayment whereas the breccia and stringer ores are dearly remobilized. The deposit is interpreted as a volcanic peridotite association type showing similarities to other Archean komatiite-associated deposits elsewhere in the world. An unusual feature of the deposit is its occurrence in the upper ultramafic unit of a cyclic sequence in contrast with the majority of Archean komatiite-hosted nickel deposits where mineralization occurs at the base of the first ultramafic unit.

DNA amplification is an important mechanism of tumor progression that allows cancer cells to up-regulate the expression of critical genes such as oncogenes and genes conferring drug resistance. Recent studies using comparative genomic hybridization (CGH) revealed increased DNA copies of 20q sequences in 7 melanoma cell lines and B archival metastatic melanoma lesions. To evaluate chromosome 20 abnormalities in more detail and to resolve discrepancies between karyotype and CGH findings, we performed FISH analysis of metaphase cells in 13 melanoma cell lines (including the 7 lines used for CGH) and 9 primary melanoma specimens by using a whole chromosome paint specific for chromosome 20. All 13 cell lines (100%) and 8/9 primary tumors (89%) showed extra copies of chromosome 20 relative to tumor ploidy. Additionally, 6/14 cell lines (43%) and 2/8 primary tumors (25%) showed translocated chromosome 20 material previously undetected by standard cytogenetics. Cytologic evidence for gene amplification was also found in one cell line, which contained an add(20)(p13), with additional DNA being derived from 20q sequences. These data suggest that overrepresentation of a gene or genes important for melanoma pathogenesis resides on the long arm of chromosome 20.

DNA sequence amplification contributes to the multistep process of carcinogenesis, and overexpression of amplified genes has been shown to contribute to the malignant phenotype. Cytogenetic analyses of human tumor cells, including ovarian malignancies, frequently show cytological evidence of DNA amplification in the form of double minutes and homogeneously staining regions. In this report, we have combined the techniques of chromosome microdissection and fluorescence in situ hybridization (P. S. Meltzer et al., Nat. Genet., 1: 24-28, 1992) to identify the composition and chromosomal origin of seven homogeneously staining regions from seven cases of ovarian cancer. Twelve specific chromosome band regions were identified as amplified including 11q, 12p, 16p, 19p, and 19q. These results provide important insights into the organization of amplified sequences within ovarian malignancies and add further to our recognition of regions likely to harbor genes important to the development or progression of ovarian cancer.

We describe an ongoing study examining the relevance of cytogenetic changes in primary and metastatic breast cancer. Tumors samples from breast cancer patients are karyotype using G-banding techniques, and all chromosomal findings, including the presence of structural and numeric clonal abnormalities, are documented in a dynamic patient data base. Information on essential clinical characteristics is collected, and patients are followed longitudinally for disease recurrence, progression, and survival. Statistical analyses will examine potential correlations between specific abnormalities and clinical features of the disease, and survival differences between patients will be examined as a function of karyotypic differences. We anticipate that this research will provide insights on the natural history of breast cancer and help direct the search for the underlying molecular mechanisms of tumor genesis and progression.

Alkalic igneous rocks of early Mesozoic age are found in both the Quesnel and Stikine terranes in the Canadian Cordillera and include both silica-undersaturated and silica-saturated types. The saturated complexes are most abundant in Quesnellia and are multiphase complexes dominated by monzonite to diorite intrusions. Undersaturated complexes are distributed through both terranes, are dominated by syenite with lesser monzonite and pyroxenite, and, when present as a single intrusion, are characterized by concentric zoning, igneous layering, and planar mineral fabrics. Both types of complex are associated with Cu-Au mineralization accompanied by potassic and distinctive sodic and calc-potassic alteration assemblages. Although undersaturated and saturated alkalic intrusions are petrographically distinct, a petrogenetic association is suggested by their spatial coincidence in some districts, and similarities in their tectonic environment and associated alteration. The undersaturated complexes represent a distinctive suite of alkalic intrusion with magmatic arc affinities, and their emplacement into both Stikinia and Quesnellia between 210 and 200 Ma suggests that these terranes were either linked at that time or have shared unusual but similar magma-generating tectonic events at identical times.

SummaryExcavation of the three Surrey hillforts of Anstiebury, Holmbury, and Hascombe between 1972 and 1977 showed a general similarity of design and function but some variation in detail. Ranging in area from 6 to 10 acres (2·3–4 ha.), they were all related to the use of the sling; two were multivallate but Hascombe was univallate. Occupation was seemingly slight and Anstiebury was possibly uncompleted. The contribution of scientific method to problems of prospecting and dating is discussed. This and the pottery evidence indicate construction within the period 200–50 B.C., most probably 100–50 B.C., and the three sites may have been abandoned simultaneously. At Hascombe a pit- or hearth-filling produced Class I potin coins and the hypothesis is advanced that the hillforts were dismantled as a result of Caesar's landings of 55 and 54 B.C. but it is emphasized that decisive proof is lacking.

SummaryExcavations at the Iron Age hillfort of Bigberry, Kent, in 1978–80 had the object of a fresh appraisal since the excavations of 1933–4 of a site customarily regarded as the first obstacle encountered by Caesar after his second landing in Britain in 54 B.C. The main defences and those of the annexe were sectioned, and a hitherto unrecorded cross-dyke also. Various magnetic anomalies located by a geophysical survey were investigated and gave evidence of internal occupation and structures. It is suggested that there was a settlement preceding the hillfort, with the cross-dyke as a possible second phase; the hillfort may have been built in the second century B.C. by newcomers from Gaul, and after Caesar's passage through Kent the occupants moved down into the valley of the Stour to the site of Canterbury, though the precise point in the second half of the first century B.C. remains uncertain.The opportunity has been taken of a simple but complete republication of the nineteenth-century discoveries of the metalwork from the site now dispersed among museums at Canterbury, Maidstone and Manchester. It is suggested that this material represents the abandoned possessions of the inhabitants and varied aspects of their life, and industrial or ritual explanations are discounted.

Renewed excavation at the Iron Age hillfort of Oldbury, near Sevenoaks, Kent, in 1983 and 1984 was designed to effect a comparison with earlier excavation in 1938 and to relate the hillfort itself to others on the Greensand of Surrey and Kent. Re-examination of the defences suggests construction in the first half of the first century B.C. and questions the supposed refortification against the Roman invasion of A.D. 43; activity at this time and later in the Roman period is thought to reflect quarrying for stone. Some evidence for internal activity was recovered, but the scale was too slight to indicate permanent occupation.

Amphitheatres, although not so ubiquitous as, say, bath-buildings, were common enough in the Roman world to attract a set of terms applicable to their very distinctive structural features. It is true that they varied in construction from a simple earth bank to an elaborate masonry building like the Colosseumat Rome. But certain characteristics were constant, and it seems useful to list the technical terms used to describe amphitheatres. Some of these are scarcely applicable to the relatively simple Chester amphitheatre, while others are etymologically rather dubious. This list itself is almost entirely confined to the structural features since there are easily accessible descriptions of the spectacles which took place within amphitheatres. Previous lists have been given by Dyggve in his description of the amphitheatre at Salona and by Heidenreich in his report on the civil amphitheatre of Colonia Traiana at Xanten.

The Teutonic Bore massive sulfide deposit occurs in a sequence of Archean mafic and felsic volcanic rocks in the northeastern Yilgarn Block, Western Australia. Felsic volcanic rocks form part of a regionally continuous linear belt consisting of locally emergent volcanic centers separated by interbedded aquagene tuffs and water-lain epiclastic sedimentary rocks. Mafic and felsic rocks in the area have been extensively intruded by gabbro and subsequently by high-level granitoids believed to be cogenetic with the rhyolitic rocks.Regionally the deposit lies in a linear zone of complex structure and lithology characterized by repeated periods of extensional tectonism. Rhyolite and cogenetic granitoids are related to earlier phases of extension, whereas subsequent activity led to the formation of a suite of saturated to undersaturated syenites and fault-bounded units of polymictic conglomerate derived largely from the rhyolite and high-level granitoids.The Teutonic Bore deposit consists of one relatively small, steeply dipping lens of predominantly banded massive sulfides (mainly pyrite, sphalerite, chalcopyrite, and galena) underlain by concordant and discordant stringer mineralization. The mineralization occurs within a sequence of pillowed basalt and tuffaceous sediment 0 to 150 m stratigraphically above rhyolitic volcanic and volcaniclastic rocks. Primary textures within the massive sulfides and underlying chert indicate depositional instability. Active growth faulting controlled the deposition of felsic epiclastic sedimentary rocks, subsequent basaltic rocks, and the development of the third-order basin which provided the site for deposition of massive sulfides. The faults probably provided the conduits for hydrothermal solutions; these fluids spread laterally and vertically prior to exhaling at the rock-seawater interface during a volcanic hiatus. Features within the local environment are compatible with regional extension. Regional extension resulted in bimodal magmatism, and the associated rifting formed basins suitable for the deposition of extensive epiclastic sedimentary rocks.The bimodal volcano-plutonic host at Teutonic is similar to many examples from the Archean of Canada, but the style of felsic volcanism, the carbonate-rich alteration, and the lead- and silver-enriched ore are most similar to deposits in the Sturgeon Lake area.

The discovery of the kiln described in the first part of this report is a pleasing instance of the value of publicity in the field of archaeology. One feature of the post-war campaign waged by the Council for British Archaeology in order to induce the general public to report archaeological discoveries was the issue to sand and gravel companies throughout the country of the illustrated pamphlet entitled Sand and Gravel in History. In due course a copy reached the Apex Sand and Gravel Limited, which has its pits by the Foss Way at North Hykeham, southwest of Lincoln. In October 1951 an employee, Mr. E. Clifton, noticed in the bank of one of the water-filled workings a pit-like structure with a scatter of pot-sherds and fragments of clay bars, some of which he collected and handed to the Manager, Mr. W. C. Acott. The latter compared the sherds with the illustrations in his copy of the pamphlet, deduced that they were Romano-British, and reported the discovery to Mr. F. T. Baker, F.S.A., at the City and County Museum, Lincoln, who, from the description given and an examination of a sample of the pottery, was quick to realize the possibility of yet another kiln in the Lincoln area.

The Cistercian abbey of Vale Royal was, as the name implies, a royal foundation and as such will be included among the buildings described in the forthcoming Ministry of Works publication, A History of The King's Works. In April 1958 Mr. H. M. Colvin approached the writer with a view to arranging the excavation of the east end of the abbey church and so completing the plan, much of which had been obtained by excavation in 1911–12. The project received the enthusiastic support of I.C.I. Salt Division, which had its offices in the present mansion of Vale Royal, and indeed it is true to say that without their very generous provision of labour, equipment, and other facilities no excavation would have taken place. It was hoped that a comparatively short campaign would suffice but in the event the excavation continued from June to December 1958; the complexity of the plan and the wholesale robbing of walls to foundation level or lower meant that an area excavation proved necessary instead of the selective trenching which had been intended.

Finds from the interesting pagan Saxon cemetery at Ruskington, 3½ miles north of the better-known cemetery at Sleaford, have been published piecemeal and, for the sake of completeness, it seems desirable to place on record certain objects acquired recently by Grantham Museum under the terms of the will of the late Dr. J. H. Gibson of Aldershot. It appears that the latter was in the neighbourhood of Ruskington in 1917 and acquired the objects from a local farmer who had previously obtained them from the gravel-pit north of the village of Ruskington, where burials have been recorded from time to time.

The parish of Riseholme lies immediately north of the Lincoln city boundary and on the east side of Ermine Street as it runs along the top of the Jurassic ridge towards the Humber. It is an area of fertile, easily worked land lying between 130 and 200 ft. above sea-level, and must have presented a sharp contrast, in prehistoric eyes, to the areas of difficult settlement on the low-lying clays to east and west. The latter no doubt came under the plough in Roman times and indeed probably formed the bulk of the territorium attached to the colonia at Lincoln after its foundation at the end of the first century; but the higher ground, with few or no trees to clear, must still have seemed desirable land to the discharged legionary.

The excavations carried out by the Lincoln Archaeological Research Committee during 1953 dealt with two sites of a very different nature, although of the same period. Yet together they provide a useful illustration of the two principal aspects of the history of Roman Lincoln and also of two types of archaeological investigation demanded in an urban centre. The first excavation, in East Bight, was deliberately undertaken in an attempt to find answers to certain problems relating to the early military and quasi-military occupation of Lincoln and was excavated methodically and without haste; the second was a hasty examination during building operations at no. 292 High Street where a structure, apparently connected with the communal life of the town in its later period of expansion, demanded immediate investigation, without the opportunity for unhurried and detailed examination.The first excavations of the Research Committee, in 1945–6, at Westgate and North Row (fig. 2), resolved once and for all the question of the general siting of the Claudian fortress of the Ninth Legion and, in particular, demonstrated that on north and west the legionary defences underlay those of the later Colonia. These conclusions suggested the possibility that the defences might similarly coincide on south and east also, where the line of the Colonia wall was known; but, as Professor I. A. Richmond pointed out, if this was so, the area of the legionary fortress would only have been approximately 42 acres whereas a minimum of 50 acres might have been expected.

The recognition of recurring sites of chromosome change in human cancers has pinpointed the location in the genome of several important growth-regulatory sequences (e.g., cellular oncogenes). This report details the finding of a recurring translocation site involving the long arm of chromosome 6 (6q) in malignant melanoma. We have observed a translocation (t) between chromosomes 1 and 6 in five different cases of malignant metastatic melanoma. All five melanomas evidencing t(1;6) involved band regions 6q11-13, while two different regions of chromosome 1 (p22, q12-q21) were shown to be translocated to 6q. In reviewing previously published cases of melanoma, an additional two cases of t(1;6) and 13 cases of other translocations to 6q11-13 have been identified. Chromosome 6q contains several biologically important gene sequences including the proto-oncogenes ros, myb, and mas1. However, based on current mapping studies, the breakpoint of this translocation (6q11-13) is not within the region encoding these sequences. By analogy to other systems, molecular analysis of the translocation breakpoints may identify a gene(s) which plays a role in melanoma tumorigenesis.