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Background The Tolat sigmoid notch classification is a commonly used classification to characterize the distal radioulnar joint (DRUJ). This classification was based on a limited assessment of the entire joint, which may lead to inaccuracies in sigmoid notch evaluation. Questions/Purposes The purpose of this study is to assess the reliability of the Tolat classification for sigmoid notch characterization. Methods The sigmoid notch of 52 models of cadaveric forearms was assessed by applying the Tolat classification to the three-dimensional (3D) modeled notch and then slices at the start of the notch (0 mm) and 4 mm more proximal. The inter- and intrarater agreement was assessed using Cohen's and Fleiss' kappa statistic. Results Agreement between iterations regardless of slices or surgeons/radiologists was moderate. Intrarater agreement between pairs of slices (0 vs 4 mm, 0 mm vs 3D, 4 mm vs 3D) was moderate, whereas agreement between all slices was slight. Agreement between surgeons and between radiologists was moderate, while agreement across all raters and slices was fair. Models described as “other” were more consistent in 3D classifications and were commonly classified as a reverse ski slope. Conclusions Classification using the Tolat scheme is fair to moderate at best. Classification of the sigmoid notch using an axial view of the distal radius may not accurately reflect the anatomy throughout the notch. Clinical Relevance The Tolat classification supplies a limited analysis of the sigmoid notch, and does not represent a comprehensive evaluation of the entire joint. Future classification systems should characterize the entire sigmoid notch.

Empirical data sets of Artiodactyla (Antilocapridae, Bovidae, Cervidae, Suidae), Carnivora (Mustelidae) and Rodentia (Sciuridae, Cricetidae, Arvicolidae, Muridae), obtained by horizontal starch el electrophoresis of 15–34 isoenzyme sstems, were used to calculate genetic distances and to construct phylogenetic trees by the following methods: Nei's D (corrected for small sample sizes) - UPGMA, FITCH, KITSCH (out of Felsenstein's PHYLIP-package); Rogers-distance - distance-Wanger tree; maximum likelihood approach (cavalli-Sforza-Edwards); maximum parsimony method (wagner); Hennigian cladogram. The results were re-examined using the statisticar methods of jackknife and bootstrap. The following problems became apparent and were studied in more detail: inconstancy of molecular evolutionary rate among taxa, non-uniformity of evolutionary rate among isoenzymes, possible convergence of alloenzymes, different evolutionary histories of taxa (radiations/bottlenecks), methodological influences sample sizes / rare alleles, comparability of data sets). The results show, that many branches of the various phylogenetic trees are fairly constant. The ambiguous position of the remaining OTU's is due to insufficient evidence in the primary data rather than to theroperties of cluster algorithms. However, since these problematic cases are also uncertain in phylogenies based on morphological characters and palaeontological results, even an increased data set may not lead to a cyear decision unless additional taxa of crucial importance are examined. Molecular evolutionary rate among taxa seems to be accelerated in some cases, possibly due to random fixation of different alleles during bottlenecks, when a highly polymorpic ancestral form underwent a series of adaptive radiations. Isoenzymes can be divided into groups with different evolutionary rates. Thus, data sets are only comparable with respect to genetic variability and differentiation, when they contain a similar amount of representatives of each of these categories.

Horn growth in the Caprinae is affected by several factors including age and nutrition, and analysis of annual horn increments can be used to interpret past events. We documented patterns of horn growth in male alpine ibexes (Capra ibex ibex) in the central European Alps and analyzed relationships between annual horn increments, weather, and plant phenology in 2 different climatic regions during 1981-1990. Age accounted for 50% of total variance in horn growth in male alpine ibexes 1-6 years of age. Horn growth differed among climatic regions and calendar years. In years with early onset of vegetation growth, horn growth was enhanced uniformly over all age classes in both climatic regions. Horn growth was a function of ambient temperature during March-May and of plant phenology in spring, implicating onset of growth of vegetation and availability of food resources. Duration of growth of vegetation was assumed to be directly related to date of vegetation onset, but further studies are necessary to test this hypothesis.

We examined 3747 teeth from 134 hares (Lepus sp.) 1 collected at 46 sites in Israel to test whether variation in epigenetic occlusal characters was linked to ecogenetic or phylogenetic factors. Collection sites encompassed a wide range of ecogeographical and climatic regimes. We compared data from Israeli hares with occlusal characters of 160 cape hares L. capensis from East Africa and 68 brown hares L. europaeus from central Europe. Only three teeth (I1 ,I 2 ,M 3 ) did not show occlusal variation. Thirty-eight occlusal characters were derived from dental variants by dichotomous (0/1) scoring. Absence of association of character states among characters of single teeth indicated a lack of morphotypes. Epigenetic differentiation among hares from northern, central and southern Israel, and the two East African, and two central European samples, was revealed by pairwise C. A. B. Smith’s ‘mean measures of divergence’ (MMD), based on frequencies of character states. Cluster analyses of MMD values revealed little epigenetic differentiation between northern and southern Israeli hares, but greater differentiation between central European and East African hares. Concordance of the MMD matrix with linear geographical distances among sampling regions was demonstrated by a Mantel test. No frequencies of character states exhibited significant changes across the climatic parameters among hares from northern and southern Israel. But the individual folding index, which expresses the degree of enamel on the occlusal surface, slightly decreased from north to south. Our results support a phylogenetic interpretation of occlusal character variation. Despite distinct differences in external appearance, hares from northern and southern Israel probably comprise a single species that encompasses two closely related geographical populations with a probable area of overlap. Israeli hares are intermediate between European brown hares and East African cape hares, with a slightly closer relationship to the cape hares.

Hintergrund: Angiotensinkonversionsenzymhemmer (ACE-Hemmer) greifen in das Renin-Angiotensin-Aldosteron-System ein, das die Aktivierung von Angiotensin II reguliert, einem endogenen Vasokonstriktor. Sie nehmen einen festen Platz in der Therapie der arteriellen Hypertonie (2. Stufe des WHO-Therapiekonzepts) und der Herzinsuffizienz bei erwachsenen Patienten ein. Die Erfahrungen bezuglich einer ACE-Hemmer-Behandlung und dem Auftreten von Nebenwirkungen sind bei Kindern im Vergleich zu Erwachsenen beschrankt. Ergebnisse: In einem Kollektiv von 49 padiatrischen Patienten, die mit ACE-Hemmern (Captopril/Enalaprilat) behandelt wurden, beobachteten wir bei 2 Kindern, 3–4 Wochen nach Behandlungsbeginn, das Auftreten von Haarausfall. Diese Nebenwirkung ist bei Erwachsenen nur in wenigen Einzelfallen und bei Kinder bisher noch nicht publiziert worden. Weitere Nebenwirkungen bestanden nicht. Die Alopezie bildete sich bei beiden Kindern nach Umstellung der Behandlung vollstandig zuruck. Schlusfolgerung: Moglicherweise wurde die generalisierte Alopezie durch Interaktionen zwischen ACE-Hemmern und dem Zinkstoffwechsel hervorgerufen. Dieser Zusammenhang konnte auch ein haufigeres Auftreten bestimmter Nebenwirkung bei Kindern erklaren, da sie uber kleinere Zinkspeicher als Erwachsene verfugen.

In order to examine a previously hypothesized influence of selective hunting on allele frequency changes at some regularly polymorphic allozyme loci in red deer (Cervus eluphus), antler characters, serving as criteria for culling, were examined in relation to electrophoretic variation in two free-ranging populations of the Vosges, Eastern France, and an enclosure in Central France. When homozygous for the allele Idh-2125, stags ≥ 2 years old had a significantly higher number of antler points (NAP). When homozygous for the allele Acp-2100, stags older than 5 years had antlers that were significantly larger for a number of traits (NAP, main beam length and circumference, coronet circumference, brow tine length). Among younger stags, all antler traits in Acp-2100 homozygotes were significantly smaller than in carriers of the alternative allele, Acp-285. Our data suggest the presence of at least two independent genetic components (one associated with early development of a high NAP, the other with generally large antler size in adults), affecting antler expression in red deer. Those genetic components, possibly major genes which are chromosomally linked with the allozyme loci studied, compensate or reinforce each other in their phenotypic effects. By playing a role in balancing benefits and costs of male reproductive success, they may be part of a genetic mechanism enabling the rapid adaptation of a population to various environmental and demographic conditions. The three populations studied originate from one another, and, based on an assessment of effective population sizes, it could be demonstrated that selective hunting for antler shape has changed allelic frequencies at the associated marker loci within a few generations.

The pattern of the occlusal surface of 1018 first lower premolars (P3) was studied in 527 brown hares (Lepus europaeus) collected in 1988 and 1989 at 21 localities in Austria. In total, 29 variants were described. For analysis of geographic variation in the P3-pattern, the locality samples were grouped into five regional units with respect to spatial distances and putative barriers for gene flow. From the primarily encountered variants. 15 dicholomized characters were created and their frequencies within the five regional units were calculated. Strong right/left dependencies of character states suggested a high degree of bilateral symmetry in each character. In contrast, character varied largely independently from one another. This indicated the absence of complex types of the P3. One character showed sex-dependence but no age dependence was found. Intraregional differences in trait frequency were found in one character. Non-metrical morphological divergence among the five regional units was revealed by using C. A. B. Smith's ‘mean measure of divergence’ and ‘percentage dissimilarity’ as distance measurements. Six pairwise morphological distances differed significantly from zero. Phenetic affinities among the five populations showed good correspondence to the geographic distribution of the samples. However, whereas the alpine chains of mountains appeared to separate the hare populations, the River Danube did not, Generally, good concordance was found between the current pattern of phenetic differentiation and earlier results of cluster analyses using non-metrical skull traits and allozymes of the same populations. This suggested that geographic differentiation of the P3-traits was largely due to random historical rather than to ecogenetic causes. Nevertheless, in one population the striking discordance between the three character-systems compared could indicate some influence of a selection pressure on certain P3-variants.

A total of 469 brown hares Lepus europaeus Pallas, 1778 from 20 sampling sites in Austria were examined for genetic diversity within and among populations by means of horizontal starch gel electrophoresis. Fourteen out of 54 presumptive structural loci were polymorphic, one of which was excluded from further population genetic analyses due to the occurrence of a null-allele.

Trifluoromethanesulfonic ( triflic ) acid reacts with naphthalene at room temperature to give a complex mixture from which five products have been isolated and identified as follows: (E)-3-benzylidene-2,3-dihydro-1H-benz[e]indene (2) (yield 15-20%), 1,2,3,4-tetrahydroanthracene (7) (c. 0.5%), 4-phenyl-1,2-dihydroanthracene (8), 3,4-dihydro-1,2′-binaphthyl (9a′), 4-(2-naphthyl)-1,2-dihydroanthracene (10) [yields of (8), (9a′) and (10) each less than 0.1%]. Also formed is (Z)-2-benzylidene-1,3-dihydro-1H-benz[e]indene (6) which is formed reversibly from (2) by the action of triflic acid. Mechanisms are proposed for the formation of these products.

Bei zwei Rothirschen und drei Rehen wurden anhand kontinuierlicher Herzfrequenzaufzeichnungen die Reaktionen auf verschiedene anthropogene Storreize unter kontrollierten Bedingungen erfast. Folgende Storreize wurden gesetzt: Personenrundgange, Pferderitte, Flugdrachen, Traktor, Feuer, Futterung, Radiomusik, Hundegebell, Motorsagenlarm, Gewehrschusse. Beim Rotwild konnten 118, beim Rehwild 114 Versuche analysiert werden. Zur Quantifizierung der Herzfrequenzreaktionen wurde ein Modell entwickelt, das sowohl die Intensitat als auch die Dauer der Herzfrequenzreaktion berucksichtigt. Fast jeder Storreiz fuhrte bei beiden Tierarten zu einer signifikanten Herzfrequenzanderung. Optische Storreize bewirkten generell eine intensivere Herzfrequenzanderung als akustische. Beim Rehwild zeigten sich sowohl individuelle, tageszeitliche als auch saisonale Unterschiede in den Reaktionen auf die Storreize, beim Rotwild konnten nur tageszeitliche Einflusse festgestellt werden. Allgemein waren die Reaktionen der Rehe auf Storreize starker ausgepragt als beim Rotwild. Bei beiden Tierarten konnte keine ausgepragte Gewohnung an die gesetzten Storreize festgestellt werden.

A total of 193 brown hares, collected from 7 sampling sites in Poland during 1986-1990 were examined for genetic variability and differentiation at 39 presumptive isozyme loci by means of horizontal starch gel electropheresis.

In order to provide a scale of genetic distances in the Lagomorpha, biochemicalsystematic relationships among Lepus europaeus, Lepus iimidus, Oryctolagus cuniculus (Leporidae) and Ochotona rufescens (Ochotonidae) were examined by horizontal starch gel electrophoresis of 38 isozyme systems. Nei's (1978) genetic distances were calculated over 58 presumptive structural loci and used for the construction of numerical dendrograms. The stability of clusters was examined by the jackknife method and by comparison to a Hennigian cladogram. All these procedures revealed a constant picture of lagomorph relationships, which is in accordance with the conclusions drawn from other evidence. Divergence times were estimated using two fundamentally different approaches. They were in good agreement with paleontological data (0.49myr between the Lepus species, 3.65myr between Lepus and Oryctolagus, 37.5myr between Leporidae and Ochotonidae), but only when calculated in different ways at low and at high taxonomic levels. The results suggest a temporal acceleration of the rate of allozyme evolution in the Leporidae due to rapid adaptive radiation of biochemically highly polymorphic taxa.

Within the rodent family Muridae, eight species of the genera Apodemus, Mus and Rattus were examined for allozyme differentiation in 29 proteins encoded by 36 presumptive genetic loci. Representatives of the families Arvicolidae ( Microtus arvalis, Clethrionomys glareolus ) and Cricetidae ( Cricetus cricetus ) were used as outgroups. Thirty-three loci were found to be polymorphic within species and differentially diagnostic between species, respectively. Rooted and unrooted dendrograms, based on various genetic distances, revealed relationships between A. sylvaticus, A. flavicollis and A. microps as well as between M. musculus, M. spretus and M. caroli , which are consistent with the results of previous investigations. In contrast, A. agrarius showed a greater genetic distance to the other Apodemus species than either Rattus or Mus . Based on a Hennigian cladogram and on results of DNA investigations performed by other authors, this result was interpreted to be due to an increased rate of allozyme evolution in this species rather than to a very isolated position within the Muridae. Concerning intergeneric relationships, a UPGMA-tree unequivocally suggested Mus to be the sister group of Apodemus , whereas the cladogram revealed the ambiguous position of this genus in relation to Mus and Rattus . As demonstrated by comparison of two fundamentally different methods for estimating divergence times, this result can be explained by a rapid separation of the genera in question during extensive adaptive radiation. As a consequence of unequal rates of allozyme evolution among taxa, use of both numerical and cladistic approaches for the evaluation of phylogenies is emphasized.

Die Aktivitaten der Enzyme alkalische Phosphatase, GOT, GPT, γ-GT und GLDH, wurden im Laufe eines Jahres bei insgesamt 17 Feldhasen in Gefangenschaftshaltung gepruft. Dabei konnten keine ausgepragten saisonalen Unterschiede festgestellt werden. Hingegen zeigte das Alter der Hasen einen signifikanten Einflus auf die Aktivitaten der alkalischen Phosphatase und der γ-GT. Bei den mannlichen Tieren waren die GLDH und die GOT signifikant hoher als bei den weiblichen. Bei der GLDH konnte eine deutliche Abhangigkeit der Aktivitat von raschen Anderungen der Umgebungstemperatur ermittelt werden.

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In seven species of the Caprini, and two species of the Rupicaprini, 23 proteins encoded by 27 presumptive genetic loci were studied by horizontal starch gel electrophoresis. An antelope, the nilgai ( Boselaphus tragocamelus ) was used as outgroup. Nineteen loci were found to be polymorphic and differential diagnostic, respectively. Phylogenetic trees were constructed using various quantitative and qualitative approaches. The largest genetic distance was detected between Ovis and Capra . The Rupicaprini ( Rupicapra rupicapra, Oreamnos americanus ) turned out to be an intermediate group between Ovis and Capra and are connected to the latter by Hemitragus jemlahicus and Ammotragus lervia . Genetic distances among Capra falconeri, Capra aegagrus and C. a. f. hircus suggest a monophyletic origin of domestic goats from the latter. The high D -value between Capra ibex ibex and C. i. nubiana gives species rank for the Nubian goat. According to biochemical-genetic data the splitting of the Caprinae into the tribes Rupicaprini and Caprini is not justified. Calculated divergence times of the main taxa (late Pliocene-early Pleistocene) correspond to palaeontological findings.

Data from an extensive research project on lagomorphs were compiled and re-analyzed from a synoptical point of view for examining the indicative function of allozymic variation. Empirical data suggested the Shannon-Weaver information index to be a better indicator of allelic diversity than expected average heterozygosity. There were differences in polymorphism among various structural and physiological classes of enzymes. Reliable estimates of gene diversity and genetic distances can be obtained only if more than 30 loci are examined. At the population level, allozymic diversity was not related to morphological variation. It was, however, indicative of increased developmental homeostasis as assessed by overall fluctuating asymmetry in non-metric morphological traits. Allozymes served well for fully resolving genetic differentiation among populations and for assessing levels of migration, whereas mtDNA and morphological data provided only additional information. The results are discussed with respect to data from other mammalian taxa.

Data from an extensive research project on lagomorphs were compiled and re-analyzed from a synoptical point of view for examining the indicative function of allozymic variation. Empirical data suggested the Shannon-Weaver information index to be a better indicator of allelic diversity than expected average heterozygosity. There were differences in polymorphism among various structural and physiological classes of enzymes. Reliable estimates of gene diversity and genetic distances can be obtained only if more than 30 loci are examined. At the population level, allozymic diversity was not related to morphological variation. It was, however, indicative of increased developmental homeostasis as assessed by overall fluctuating asymmetry in non-metric morphological traits. Allozymes served well for fully resolving genetic differentiation among populations and for assessing levels of migration, whereas mtDNA and morphological data provided only additional information. The results are discussed with respect to data from other mammalian taxa.

Morphological characters in red deer (Cervus elaphus), which serve as criteria for selective hunting, were examined in relation to electrophoretic variation in three populations from the Vosges in eastern France. From the polymorphic loci examined, certain alleles at Idh-2, Me-1 and Acp-1 showed significant associations with a special development of body and antler characters selected for by hunters. Idh-2(125) was associated with larger hind foot length in females and a higher number of antler points in males. Me-1(90) and Acp-1(100) were associated with small spikes. The populations studied differed from one another in the duration and intensity of selective hunting and the increase or decrease in the respective allele frequencies could be explained by selection for large body size, a high number of antler points and against small spikes in yearlings, rather than by genetic drift. Among other morphological characters examined, the length of the main beam was significantly associated with the allele Acp-2(100). In contrast, no associations could be detected between overall heterozygosity and the development or the degree of asymmetry (in paired structures) of any of the morphological traits in question. Although no obvious differences in the overall values of polymorphism or heterozygosity were found between the populations, selective hunting leads towards a change in allele frequencies and eventually to the loss of one or the other rare allele.

International audience

Trifluoromethanesulfonic ( triflic ) acid reacts with naphthalene at room temperature to give a complex mixture from which five products have been isolated and identified as follows: (E)-3-benzylidene-2,3-dihydro-1H-benz[e]indene (2) (yield 15-20%), 1,2,3,4-tetrahydroanthracene (7) (c. 0.5%), 4-phenyl-1,2-dihydroanthracene (8), 3,4-dihydro-1,2′-binaphthyl (9a′), 4-(2-naphthyl)-1,2-dihydroanthracene (10) [yields of (8), (9a′) and (10) each less than 0.1%]. Also formed is (Z)-2-benzylidene-1,3-dihydro-1H-benz[e]indene (6) which is formed reversibly from (2) by the action of triflic acid. Mechanisms are proposed for the formation of these products.

ln 10 species of the Bovini, 15 proteins encoded by 15 genetic loci were studied by horizontal starch gel electrophoresis. Five of these loci (Ldh-2, Pgd, Es, Acy-l, Gpi) were found to be polymorphic in at least one of the species examined. The results on the biochemical systematics of the Bovini suggest, that the yak ( Bos mutus ) is most closely related to the cattle ( Bos primigenius ), followed by the gaur ( Bos gaurus ) and the banteng ( Bos javanicus ), which form a separate cluster. The bisons (Bison bison and Bison bonasus) are much more distantly related to the cattle than the yak, the gaur or the banteng. The African buffalo ( Syncerus caffer ) and the anoa ( Subalus depressicornis ), having their branching point somewhat earlier than Bos and Bison , show a remarkable genetic distance from the latter. The extent of genetic variability found within species is discussed with respect to conservation and breeding in captivity.

In this paper, we derive essentially nonunique closed-loop Nash equilibria for a class of nonzero-sum differential games with a unique and degenerated feedback Nash equilibrium.

Interspecific compatibility and incompatibility have been examined through the genus Populus. General methods of manipulation have been developed to break the incompatibility barriers. These methods are described and a hypothesis is put forward to account for the results. This proposes that at least two factors are involved, one attached to the pollen (P) and one to the stigma (S), and that the interaction of these (PS) is critically involved in the total process. Implications for future plant breeding are discussed.

Seven cases of early gastric carcinoma are reported. This condition by definition refers to a carcinoma confined to the mucosa and submucosa only. The definition depends upon the depth of spread and not the surface area covered by tumour or the period over which it is believed to have been present. Each patient had a history indistinguishable from one of benign ulceration. All seven patients had barium meal studies, and in only two was the possibility of malignancy raised. In the other five patients the ulcers demonstrated radiologically were considered benign. Fibreoptic endoscopy was done in six cases; in three the appearances were suspicious of malignancy, and in the remaining three the lesions appeared benign. Biopsy specimens taken at endoscopy contained carcinomatous tissue in all six cases. The patients all had partial gastrectomy, and no recurrence has yet been found. The longest follow-up period is 36 months.

SUMMARY Vegetative propagation of Eucalyptus has been achieved in several different ways, mainly by grafting, but air-layers have also been successful and cuttings will also root if sections cut from stems of very young seedlings are used. Current techniques are adequate for seed orchard establishment, horticultural use, and experiment, but further development is necessary to prescribe methods cheap enough for the production of general planting stock.

SUMMARY A species of basidiocarp has been seen in constant and specific association with mycorrhizal Ericaceae. These basidiocarps are shown to be serologically related to pelotons of the mycorrhizal fungus.

Pretreatment of stigmas of poplar flowers with hexane or ether promoted hybridization between normally incompatible black and white poplar species. Success rates, as measured by setting of fertile hybrid seed, exceeded 95% of those resulting normally from compatible crosses. Results suggest the existence of some incompatibility factor, possibly of a lipoid nature, located on the stigmatic surfaces.

Fifteen cases of solitary ulcer of the rectum are described. The patients complained mainly of rectal bleeding, discomfort and passage per rectum of mucus. The lesion is most commonly situated on the anterior wall of the rectum and can be red and granular, nodular or ulcerating. Peolapse was found in nine cases. The histological lesion is similar to that seen in rectal prolapse. The condition can be mistaken for colitis, adenomatous polyp or carcinoma. Reassurance, defaecation reeducation and dealing with the patients'emotional problems alleviated the condition in some cases. Surgery to remove a prolapsing segment was performed in one case only.

Summary The difficulty of controlling variceal haemorrhage has led to the recent development of methods designed to sclerose the bleeding vessels. This study describes the application of percutaneous transhepatic portal catheterization with emboiisation and sclerosis of varices in eight consecutive patients admitted with bleeding oesophago-gastric varices. Portal hypertension was documented and varices demonstrated in each case. Bleeding ceased rapidly in seven patients, two patients rebled 1–3 weeks after the procedure, and five patients were subsequently discharged from hospital. In no instance was death related to continued gastrointestinal haemorrhage. Initial experience with transhepatic embolisation of bleeding oesophago-gastric varices indicates that this technique is effective in controlling variceal haemorrhage.

Role of Pollen-Wall Proteins as Recognition Substances in Interspecific Incompatibility in Poplars

A growth regulator (G) occurs at high concentrations in adult leaves of E. grandis Maiden. Low concentrations of G are present in juvenile leaves of this species and also in adult leaves of some other Myrtaceae. Low concentrations of G (5×10(-6) and 10(-5) M) promote rooting in mung-bean cuttings and elongation in Avena coleoptile sections; high concentrations (5×10(-4) M) inhibit. These and other bioassay results indicate that G may have auxin-like activity.

Three closely related growth regulators (G) that are present in some myrtaceous plants were examined for possible anti-transpirant effects. The bioassay material involved cuttings of mung bean and Eucalyptus rupicola. Stomatal resistance was determined by a diffusion porometer. Water loss was equated with water uptake by the cutting over a 24-hour period. In both bioassays, G reduced water loss. The reduced water loss was associated with stomatal closure. This anti-transpirant effect of G was five to ten times less than that of abscisic acid. The stomatal resistance to the diffusion of water vapor from mung bean leaves increased within 1 hour of application of G. Marked stomatal closure occurred after 6 hours when 5 to 7 micrograms of G had accumulated in the leaves. These results and earlier evidence, suggest that G growth regulators are involved in the water economy of Eucalyptus and perhaps other related genera.

The available physiological evidence suggests that ontogenetic ageing of E. Grandis seedlings involves a direct and quantitative association between decreased rooting ability of stem cuttings and increased levels of a rooting inhibitor in the tissue forming the base of the cutting. As detected by bioassay, this inhibitor is present only in adult tissue, which very rarely forms roots from stem cuttings. It is absent in easily rooted seedling stems of all Eucalyptus species tested, but it is also absent in the easily rooted adult tissue of the exceptional species E. deglupta. The ability of seedling cuttings of E. deglupta to root very easily in water provides an appropriate bioassay for monitoring the presence of inhibitor in other Eucalyptus species.