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Descriptions of the male and pupa of Thienemannimyia pseudocarnea n.sp. are given and its relationship with some other members of the carnea Group are discussed.

SUMMARY. The chironomid fauna of a chalk stream in southern England is described from 1 year's catches of emerging adults and 2 year's quantitative samples of larvae on Common Clubrush, Schoertoplectus lacustris. The number of species in eaeh higher taxon as adult males and larvae on Schoenoplectus were: Tanypodinae, nine and three; Diamesinae, two for both; Orthoeladiinae, 26 for both; Chironomini. twelve and six; Tanytarsini, seven and five, respectively. A total of 66 species was recorded for both life stages. Adult Orthocladiinae were caught throughout the year. Tanytarsini were absent for a few weeks in winter, and Tanypodinae and Chironomini were caught for shorter periods in warmer months. Chironomids 93.5% of the total invertebrates on Schoenoplectus. Life histories are deseribed for seven speeies that formed 91% of the identified chironomids (32% of the total were unidentifiable first and second instar larvae). Four of these life histories appear for the first time. All seven species were multivoltine and had continuous recruitment for part of the year. The species diversity of larvae was mostly in the range 1.5–3.0 and it was determined more by equitability than by species richness. The numbers of chironomids through time were dependent on the weight of detritus on the leaves (r2= 0.69) and the availability of detritus therefore partly controlled their population size.

An emergence trap was operated for two years on a chalk stream in southern England. AH species of aquatic Diptera except Simuliidae and females of Chironomidae and Psychodidae were identified. Chironomidae formed 97% of the total Diptera and 81 species were recorded. Some of the nine species of Ceratopogonidae were occasionally numerous. No other family was important. Differences in the fauna between years were related to changes in the flow regime. Numbers of both species and individuals of Chironomini and Tanypodinae were notably higher in a severe drought than in more typical conditions. Many species had long flight times which in some cases may have been due to polyvoltinism. A comparison of temperatures in streams in which Chironomidae had been studied in southern England and Germany suggested that more generations could be completed in the more temperate English streams. Neozavreliafuldensis and Paratanytarsus lauterborni were new to Britain and a species of Palpomyia may be new to science.

1. Three species of Tanypodinae (Chironomidae) were found in an acid and iron-rich stream in southern England. Maximum abundance was achieved in summer and they were sparse at other times. Individuals were aggregated on the stream bed and were overrepresented in accumulations of leaf litter. 2. The diets of all three species consisted of a mixture of prey (prominently detritivorous chironomid larvae) and detritus. More detritus and fewer prey were taken in winter than in summer. 3. When comparing large tanypod species with small and, intraspecifically, late instars with early, the proportion of guts containing prey increased with increasing body size. 4. Stonefly larvae were more prominent in the diet of Zavrelimyia barbatipes (Kieffer) in summer than in winter but for the other two species the reverse was true. A bigger proportion of Trissopelopia longimana (Staeger) guts contained prey in early summer than in August whereas more Macropelopia goetghebueri (Kieffer) guts contained prey in August. This was apparently a consequence of seasonal differences in the distribution of body size among the populations of these two species. 5. The stream contains two further common predators, Plectrocnemia conspersa (Curtis) and Sialis fuliginosa Pict. These are important predators of tanypod larvae but might also compete with them since they severely deplete populations of prey taken in common. 6. Analysis of the food-web in Broadstone Stream reveals remarkably high values of connectance (C and Cmax) and of species richness times connectance (SCmax). Such characteristics are theoretically associated with fragile and dynamically unstable food webs, and may be found in ‘constant’ environments. There is also an apparently unusual prevalence of omnivory in the community.

The littoral macrozoobenthos (MZB) of three northeastern Pennsylvania lakes was sampled seasonally from summer 1981 until summer 1983, to determine if any changes were occurring in response to acid deposition. In the acidified lake (total alkalinity ≤ 0.0 μeq L−1) the mean pH decreased from 5.5 in 1981 to 4.2 in 1983. Chironomidae comprised 71.30% of the MZB numbers and 19.6% of the wet weight. Over the study period the wet weight of Chironomidae increased (p < 0.04) as did the total numbers of Chironomidae in general (p < 0.01) and Tanytarsini (p < 0.01) in particular. Total numbers of MZB also increased (p < 0.02) in the acidified lake, but there was no significant change in the number of taxa, diversity or total wet weight. In the moderately sensitive lake (total alkalinity 47.4 μeq L−1, mean pH 6.1) Chironomidae were numerically (43%) dominant but Odonata (18.6%) and Mollusca (12.7%) dominated wet weight. There were no significant changes in the MZB of the moderately sensitive lake over the study period. In the least sensitive lake (total alkalinity 190 μeq L−1, mean pH 6.6) the Amphipoda (31.3%) and Chironomidae (27.3%) together provided 58.6% of the MZB numbers, and the Mollusca formed 55.1% of wet weight. Wet weight at the least sensitive lake was higher (p < 0.01) and there were more Ephemeroptera, Pelecypoda and Gastropoda than at the other two lakes. There were no differences in total numbers, diversity or number of taxa among the three lakes.

Sixteen floating, box type emergence traps, each covering 0.1 m2, were placed along 150 m of a third-order stretch of the Bigoray River, a slow-flowing, vegetation-choked, brown-water muskeg stream. Effects of trap design, trap shading, length of sampling interval, and stream velocity on the number of midges caught was examined. Of the 112 species of Chironomidae caught, 32 species made up 90% of the catch and their emergence phenology is described in detail. There were more rare species than expected from Preston's lognormal distribution. Percentage of Bigoray species belonging to Tanypodinae, Orthocladiinae, Chironomini and Tanytarsini was 18%, 43%, 20%, and 19%, and was compared with 27 other studies on lotic chironomids. During the 140-day emergence period an average of 19.3 × 103 chironomids emerged per square meter of stream. Based on changes in male:female ratios throughout a species emergence period, it was postulated that 30% of the Bigoray chironomid species were univoltine, 50% were bivoltine, and 20% were trivoltine.

Some streams near Dorset in south-central Ontario suffer from acid precipitation via run-off and seepage from thin soils with little buffering capacity. A spring-summer survey of eight headwater streams revealed some characteristics of their insect communities which could be correlated with pH. The streams could be divided into three groups according to pH and community structure. In the most acid group (annual pH range 4.3–4.8), Ephemeroptera were absent from two streams although mature Leptophlebia were collected just after spring thaw from the most acid one (pH 4.3–4.5). One of these three streams also lacked Plecoptera but the others had two or three genera, all shredders. The second group of three streams (pH 5.0–6.3), with one exception, did support Ephemeroptera (3–4 genera) and Plecoptera (1–4 genera), most of the latter being shredders. In all six of these acid streams, Trichoptera were more diverse and more dense than Ephemeroptera and Plecoptera; again, shredders were clearly dominant, especially the limnephilid caddisfly, Frenesia difficilis (Walker). These six streams also had similar chironomid communities (densities were an order of magnitude higher than other insects). Dominance by Chironomini and abundant Tanypodinae typified the most acid streams. In contrast, the two streams in the third group (pH 5.3–6.7) had richer and more balanced communities in general with relatively fewer shredders (no Frenesia), more collectors, and fewer Chironomini and Tanypodinae. As a field experiment showed that autumn-shed leaves decomposed more slowly in acid than in non-acid streams, summer-growing shredders may benefit from the pulse of acidity at snowmelt.

Eighty-seven species of chironomid larvae were collected from streams in the Big Thicket area of southeast Texas. Samples of leaf debris, wood debris, and sand were taken from the streams and the larvae occupying the substrates were analyzed. Four subfamilies were represented including Tanypodinae (12 species), Diamesinae (2 species), Orthocladiinae (30 species), and Chironominae (43 species). Dominant species included Lopescladius sp., Polypedilum ? convictum, Polypedilum ? halterale, Cladotanytarsus sp. group A, Rheotanytarsus sp., and Tanytarsus sp. 2. A brief account of the habitat and the distribution of each species encountered during this study is given.

Adult populations of nuisance chironomid midges were collected daily over a 2-year period by using New Jersey light traps at five waterfront locations of a city bordering the southern shore of Lake Monroe in central Florida. Species of Chironominae, Glyptotendipes paripes Edwards, Chironomus crassicaudatus Malloch, Chironomus decorus Johannsen, and Tanypodinae spp. (mostly Coelotanypus scapularis (Loew), Coelotanypus concinnus (Coq.), and Procladius sublettei Roback) were the most abundant midges. The 2-year maximum nightly catch of these midges taken in active traps amounted to 184,133, 134,233, 3,990, and 16,191 adults, respectively. Partitioning of the total sum-of-squares in an analysis of variance indicated that catches were relatively homogeneous over the trap locations. Time of year (date) and differences in phenology among the studied species of Chironominae and subfamily Tanypodinae were the factors contributing the greatest amount to the variation in trap catches. Autocorrelation analysis identified a weak periodicity in catches of ca. 600 degree-days above 0°C, which may correspond to the developmental time for a generation of the predominant species.

The sequence of qualitative and quantitative changes in the chironomid fauna of Laurel Creek Reservoir over the thirteen years of its existence are presented. There was a substantial decrease in the average numerical abundance Pram 1967 (6303m−2) to 1968 (3373m−2), and it has remained stable since (3166m−2 in 1975, 2856m−2 in 1980). There have been distinct changes in the faunal numerical abundance, although the genera have remained the same. In 1967, the Chironomini (Chironomus >Glyptotendipes) comprised 95% of the total throughout the year. In 1968, the Chironomini dominated (68%) the Tanytarsini increased (24%) and the Tanypodinae (6%) and Orthocladiinae (2%) remained low. In 1975, the Chironomini (Chironomus > Glyototendipep ≈ Cladopelma) (72%) and the Tanypodinae (Procladius) (21%) increased, the Tanytarsini decreased (5%) and the Orthocladiinae remained low (2%). By 1980, the Tanypodinae (Procladius) had become dominant (60%) while the Chironomini (Chironomus > Cladopelma > Glyptotendipes) ...

Diel drift samples utilizing nets with mesh size less than 200 microns were taken in Linesville Creek, Pennsylvania, an eastern deciduous forest stream, and Inlet Run, Wyoming, an alpine snow melt stream. Identification of drifting Chironomidae larvae to lowest level taxonomic categories indicated 51 species or species group categories representing 51.95% of the total insect drift in Linesville Creek and 18 species or species group categories representing 70.47% of the total insect drift in Inlet Run. Orthocladiinae were the predominant larvae in the drift in Linesville Creek, with 19 species comprising 43.84% of the Chironomidae drift. In decreasing abundance were Chironomini (12 species, 40.36% of Chironomidae drift), Tanytarsini (10 species, 8.89%), and Tanypodinae (10 species, 6.91%). By contrast, Diamesinae were the predominant larvae in the drift in Inlet Run, (5 species, 71.43%) followed by Orthocladiinae (10 species, 27.25%), Tanytarsini (2 species, 1.20%), and Podonominae (1 species, 0.12%). Comparison of drift composition with substrate samples and/ or emergence data indicated a close relationship between relative abundance in drift and relative abundance in the benthos. Behavioral drift patterns with nocturnal peaks were seen for 3 species or species groups in Linesville Creek. Four species with diurnal drift peaks were present in Inlet Run. Analysis of the size distribution of drifting larvae indicates that a mesh size as small as 200 microns is required to resolve diel drift patterns. It is postulated that random factors greatly influence the apparent diel drift pattern of Chironomidae when nets with mesh size in excess of 400 microns are employed in drift studies. Conflicting literature reports of behavioral drift for Chironomidae may be due to differing species composition of drifting larvae and net mesh size related artifacts.

The response of littoral invertebrate populations to exclusion of fish (principally small bluegill sunfish, Lepomis macrochirus) from allochthonous detritus habitats in Bays Mountain Lake, Sullivan County, Tennessee, was monitored from mid-March until mid-June 1980. The following taxa reached densities within fish exclosures that were significantly higher than those in control nets on at least one occasion: Alona, Chydorus, and Eurycercus (Cladocera: Chydoridae); cyclopoid copepods; non-predaceous midges (Chironominae and Orthocladinae) and predaceous midges (Ceratopogonidae and Tanypodinae). Evidence for the direct effect of fish predation on prey densities was most convincing for Chydorus during their "spring crash" in early April, Eurycercus during a less dramatic decline in late April to early May, and for non-predaceous midges after three months of fish exclusion in mid-June. Each of these taxa was an important component of the diet of small bluegill sunfish during the relevant time periods.

The tracheal systems of 142 chironomid larvae (42 species) were examined. These tracheal patterns showed considerable variation, both between subfamilies, and within a particular subfamily. The dorsal trunks, lateral trunks, dorsal anastomoses, and subcuticular tracheation were the major tracheal components examined in this study. Orthocladiinae, Diamesinae and Tanypodinae larvae exhibit the most extensive tracheal systems differing mainly in the placement of anastomoses. In some Podonominae species the tracheal system extends only to abdominal segment 8, where the trunks merge to form an open spiracle. Other podonomines, though not examined, are apneustic. The Chironominae tracheal system appears to extend the entire length of the larva, but only certain portions of it are filled with air. In Tanytarisini air is present in the thoracic tracheae and the terminal abdominal tracheae. In some Chironomini, air is present only in the thoracic tracheae, while other members of this tribe exhibit the 'Tanytarsini' pattern. The phylogeny of the Chironomidae, and the effects of environmental factors on the tracheal system are discussed.

Dead Man Lake (elevation 2,800 m) is one of several hundred shallow lakes on the flat, rolling crest of the Chuska Mountains. The lacustrine sediments consist of 7 to 10 m late—Pleistocene sandy silt or fine sand beneath only 0.1 to 0.3 m Holocene organic mud. Five faunal zones in the Pleistocene sediments contain distinctive assemblages of Cladocera and larval Chironomidae. The Chydoridae were the dominant Cladocera during Wisconsin glaciopluvial time, but only two or three species occurred in any of the zones. Tanytarsini and Procladius (Tanypodinae) were usually the dominant Chironomidae; populations of Orthocladiinae and Chironomini were smaller and chronologically discontinuous. The Pleistocene fauna is an impoverished as in other Pleistocene lake sediments and in modern arctic lakes. Therefore the faunal assemblages support the palynological evidence for alpine conditions on the crest of the Chuska Mountains during Wisconsin glaciopluvial time. The organic mud deposited since the end of the Pleistoc...

A study on the chironomids of Linding A showed that 67 species were represented. 12% of the species belong to the subfamily Tanypodinae, 63% to the Orthocladiinae and 25% to the Chironominae. On th...

Several aspects of overwintering were studied in the larvae of selected species of chironomids living in shallow ponds.In two species (Einfeldia synchrona Oliver and Polypedilum simulons (Townes)) from a pond near Ottawa, Ont. (45° N.), development ceased in mid-November and the gut was subsequently evacuated. A species of Chironomus from another pond did not evacuate the gut although feeding ceased. In the laboratory, larval development of Einfeldia collected at any time of year continued except at low temperatures, but pupation occurred only at long day-lengths. Seasonal changes in horizontal distribution were apparently not primarily related to possible winter effects, but to water depth changes. Larvae of E. synchrona penetrated deeper mud layers during winter (as well as in midsummer); those of P. simulans were always confined to superficial mud layers.The later instars, at least in Chironomini, usually predominated during the winter, but season to season variation was marked. In the arctic all instars except the first were present. Closed winter cocoons were found in several temperate and arctic species. Some were made by sealing an existing tube, others by building a more or less transparent tightly applied cocoon. Inside these cocoons, the larvae were tightly folded in different ways more or less characteristic of the species. At Ottawa, cocoons were usually formed well after ice cover, and partly in response to low temperatures. Larvae showed a lower water content in winter than in summer. In the arctic, larvae were also somewhat dehydrated in winter, but there was in addition a different type of dehydration which resulted in shrivelling.There was no significant ability to resist freezing by inoculation with ice. Freezing tolerance was found in some temperate and all arctic larvae and was temperature- and time-dependent. In temperate areas, freezing-tolerant larvae were nevertheless freezing-susceptible in summer.These studies and previous findings are discussed in relation to winter habitat conditions and the remainder of the life-cycle. Generalizations are compromised by complex inter- and intra-species differences and by habitat variations. Freezing tolerance is widely distributed through the genera of most subfamilies except the Tanypodinae, and is probably most general in the Orthocladiinae. Since there are few specializations of larval physiology which explain such tolerance, the Chironomidae can probably be considered as largely pre-adapted to a rigorous winter environment.

During a study of the Chironomidae in Marion Lake, British Columbia, 13 speicies representing three subfamilies (Chironominae, Orthocladiinae, and Tanypodinae) were found parasitized by mermithids. Only two species of mermithids were found, Hydromermis contorta and Limnomermis bathybia . The former species appears to have two generations per year. The highest infection levels were found in Chironomus modestus , which, however, does not appear to be a physiologically suitable host.

This preliminary report on a revision of the Tanypodinae of Africa south of the Sahara is based mainly on the collection of imagines in the British Museum (Natural History). It has been possible to re-examine most known species, in addition to studying new species, and to classify them according to the scheme proposed by E. J. Fittkau. Most species fit into his genera but a few new ones will have to be erected. The distribution of species is discussed.

The commonly used preservatives for chironomid larvae were found to cause regurgitation of the gut contents, the incidence of regurgitation being higher when the gut in at least two of the thoracic segments was full. The Tanypodinae larvae regurgitated more frequently than others, because of differences in their gut morphology, the nature of the food ingested, or a combination of both. Handling of the larvae also caused regurgitation. Increased predation by Tanypodinae larvae appeared if there was a delay between collection and preservation or examination of the samples. These problems can be overcome by rapidly freezing the samples immediately in either powdered solid carbon dioxide or liquid air.

Additional references and information on most of the topics covered here may be found in this excellent book. Even with this restriction a high degree of selection is necessary and most of the papers on genetics, physiology, pro­ ductivity and biomass, and fish food are not considered. Many of the papers cited have been chosen because they are most likely to be useful for fur­ ther reference. CLASSIFICATION It seems necessary to comment briefly on the reasons for the confusion which exists in the classification of the Chironomidae. Part of the confusion arises from the dual use of two family names. The name Tendipes Meigen 1800 was used rather than Chironomus Meigen 1803 by many taxonomists as the type genus of the family. A recent ruling of the International Com­ mission on Zoological Nomenclature has suppressed the Meigen 1800 names in favor of his 1803 names (se e Fittkau 39). As a result, the name Ten­ dipes was suppressed in favor of Chironomus, and similarly Pelopia was suppressed in favor of Tanypus. This action means that the correct name of the family is Chironomidae not Tendipedidae. Furthermore, it also estab­ lishes that the subfamily names Chironominae and Tanypodinae are correct. Although not covered by a ruling it is generally accepted that Orthocladii­ nae be used in place of Hydrobaeninae. Tanytarsus has been used as a ge­ nus in the tribe Chironomini, but another ruling (Bull. Zool. Nom. 18, Opin­ ion 616) established it as a genus in the tribe Tanytarsini. The classification of holometabolous insects presents special difficulties because the characteristics of all the life stages must be considered. Differ­ ent ecological requirements of each stage often result in greater diversity, both ecological and morphological, in one stage than in another. The adults of the Chironomidae are usually more uniform in stru cture than are the immature stages, especially the larvae. The adult stage is somewhat ephem

Drift nets were placed in the stream for 24 hour periods twice each month. Pupal exuviae and larvae were examined. Results of 6 months of sampling are given. Five major taxa of Chironomidae were found: Chironomini (dominant), Orthocladiinae, Tanytarsini, Tanypodinae, and Diamesinae. Forty-two genera were identified. Future work is outlined.

The Chironomid fauna of the rivers Karun and Zayanderud in Iran was investigated by a study of drifting pupal exuviae. A total of sixty-one taxa is recorded. The Tanypodinae, Orthocladiinae and Chironominae are well represented. The fauna is dominated by the Orthocladiinae. Some rare and interesting types are recorded and notes are given on taxonomic difficulties encountered.

Beaver (Castor canadensis) affect the benthic invertebrate community of small woodland streams in Quebec through habitat modifications. Their activities influence community structure through the replacement of lotic taxa by lentic forms and community function by increasing the absolute importance of collectors and predators while decreasing the relative importance of shredders and scrapers in impounded sites. At our study site during the 1983 ice-free season, standing stocks of coarse particulate organic matter (>1 mm) were 2–5 times greater (P

This paper deals with the abundance and distribution patterns of profundal zoobenthos from 81 Spanish reservoirs which were sampled during mixing and stratification periods in 1973/75 and again in 1987/88. Our main aims are to explore the regional variability and to compare these two surveys, separated by 14 years. The densities of three major benthic groups were considered: Oligochaeta, Tanypodinae and other Chironomidae (basically Chironominae with some Orthocladiinae). While differences between reservoirs were highly significant for all three groups, differences between basins were only reflected by chironomids. Differences between surveys depended on the benthic group and the season. Between 1973/75 and 1987/88, Oligochaeta densities halved significantly in winter (all basins), tanipodins increased 1.7-fold in summer (northern and central Spain), while other chironomids significantly increased 1.8-fold in summer (northern and central Spain) and 1.6-fold in winter (all basins). The increase in chironomids accompanied by the decrease in oligochaetes was partly attributed to better oxygen conditions in the last survey.

Anatopynia vittigera Edwards is transfered to Alotanypus. The male and female of A. vittigera comb. nov. are redescribed and immatures are described and illustrated. A cladistic analysis including one species of each Macropelopiini genus was conducted in order to assess the phylogenetic position of Alotanypus and to provide the first phylogenetic hypothesis for the genus. Adults and immatures were included in the analysis where discrete and continuos characters were considered. The cladistic analysis demonstrated that Alotanypus is a monophyletic genus, with Guassutanypus oliveirai as the sister group. Fil: Siri, Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentina Fil: Donato, Mariano Humberto. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Orpella, German Hugo. Administración de Parques Nacionales. Delegación Regional Patagonia; Argentina Fil: Massaferro, Julieta. Administración de Parques Nacionales. Delegación Regional Patagonia; Argentina

Aim The aim of the present study, was to apply two biological indexes based on benthic macroinvertebrates (BMWP and ICB RES-P) using as model the Itupararanga Reservoir to know what the advantages and disadvantages of the application of each index in that environment. Methods The methodology consisted on three stages: 1) macroinvertebrates sampling and determination of limnological variables in situ, and sorting of the organisms in laboratory, 2) taxonomic identification of organisms and 3) determination of the saprobic degree for the collection sites and effectiveness of the application of the BMWP (Biological Monitoring Working Party score system) index and the Benthic Community Index created by CETESB (Environmental Sanitary Company of State of São Paulo) for deep regions (ICB RES-P index). Results The study was performed over two periods (spring/summer and autumn/winter), and 8,841 organisms were sampled and divided in 17 families. The Chaoboridae (genus Chaoborus), Chironomidae (subfamilies Chironominae and Tanypodinae) and Tubificidae families had the most abundant taxa. The saprobic degree of the Itupararanga reservoir region resulted in the general classification of the reservoir as β-α mesasaprobic (βms- αms), considered critical due to its organic charge content. The BMWP index was adapted to the sample points and the scores subsequently obtained ranked the reservoir as category V, representing very poor water quality. The ICB RES-P index classified the sample points in the spring/summer period as having regular water quality, and the autumn/winter period as having good water quality. Conclusions From previous findings, it can be concluded that further study and refinement of the components of both indexes are required in order to effectively assess the quality of water in reservoirs.

Diversity and biomass of Chironomidae larvae were studied between January-November 1993 and March-November 1994 in an impacted lagoon in Rio de Janeiro, Southeastern Brazil, in an attempt to establish the ecological consequences of anthropogenic eutrophication processes. Nine hundred and seventy-five organisms belonging to the Tanypodinae, Orthocladiinae, and Chironominae were collected. Polypedilum (62%) and Chironomus (58%) were the most common genera found in the limnetic and littoral zones.

The attraction of pestiferous species of adult Chironomidae to commercially available lamps of various colors and wattages was studied by employing New Jersey light traps along the shoreline of a central Florida lake. Glyptotendipes paripes Edwards, Goeldichironomus holoprasinus Goeldi, Chironomus crassicaudatus Malloch, and species of Tanypodinae were predominant in the collections. A comparison of 100-W incandescent lamps showed that white was preferred over yellow, and both were preferred over red, orange, green or blue. Analysis of deviance indicated that these differences were due primarily to differences in intensity (lux), although smaller effects of color and differences in response among species were detected. No differences were observed in preference between 60-W white incandescent or fluorescent lamps. These results were consistent with previous laboratory studies, and indicate that manipulating light intensity, rather than color, may be more appropriate in the overall development of an integrated control strategy of nuisance chironomid midges.

The adult male, adult female, pupa, and larva of Hudsonimyia parrishi n. sp. are described. Characters are given to distinguish H. parrishi from the other member of the genus, H. karelena Roback. The generic diagnosis for Hudsonimyia Roback is emended to include the new species. The habitat and aspects of the ecology of the immature stages are discussed.

The present paper is a continuation of our previous reports on Iowa species of the subfamily Tanypodinae (Hauber 1945; Hauber and Morrissey 1946). It is the object of this paper to list the species of the subfamily which we have not already reported, to record hitherto undescribed stages in the life histories of some of these midges, and to correct the misidentification of our earlier papers. The author wishes to thank Dr. U. A. Hauber for his aid in planning th-is paper and particularly for diagnosis of some of the difficult specimens.