ZOOLOGY Sectional Meetings Details of the technical section meetings follow. Section name, time and location of meeting, presiding officer, title of paper, and author, address and abstract are listed. See map for building locations. Business meetings are scheduled for each section. An important item of business is the election of a Membership Chairman for the Section who automatically succeeds to the office of Vice President the following year. A. ZOOLOGY MORNING SESSION Bareis Hall B4 TIMOTHY S. WOOD, Presiding THE DISTRIBUTION OF NAIADES IN THE VERMILION RIVER OF NORTH CENTRAL OHIO WITH REFERENCE TO SOME ECOLOGICAL FACTORS. MOLLUSCA: BIVALVIA: UNIONIDAE g-30 Raymond E. Bowers 400 E. Oakland Avenue Columbus, Ohio 43202 Thirteen species of naiades were collected from the Vermilion River in 1968, 1969, and 1978. There was a sporadic distribution in a variety of habitats. Most naiades were collected from substrates that were a combination of sand and gravel in association with either mud, clay, or bedrock. Higher gradients appear to limit the distribution of some naiades within the Ver- milion River, perhaps due to a limitation of the fish-host or the juvenile naiades. The pres- ence of certain naiades in the Vermilion River might best be explained by the drainage patterns during the retreat of the last glaciation, for they have not been reported from Lake Erie. AQUATIC GASTROPODS OF THE BASS ISLAND REGION OF WESTERN LAKE ERIE: A HALF CENTURY OF CHANGE. Carol B. Stein, Museum of Zoology, The Ohio State University, 1813 N. High Street, Columbus, OH 43210. 9:45 Fourteen collecting stations established in western Lake Erie by C.A. Dennis during the summer of 1927 were re-sampled in 1977, using similar quantitative techniques. Relative population densities of each species at various depths and distances from shore were determined, and are compared with those of 1927. Major alterations of habitat at several sampling sites are related to the faunal changes discovered. On the basis of the data obtained in this study, projections of future changes in Lake Erie gastropod populations are made. ZOOLOGY RELEASE AND SETTLING OF LARVAE IN SELECTED SPECIES OF PLUMATELLID BRYOZOA. 10:00 Michael W. Zimmerman and Timothy S. Wood, Department of Biological Sciences, Wright State University, Dayton, Ohio 45435. The release of sexually produced larvae of freshwater bryozoa occurs in Ohio during the summer months. However, the actual dates and duration of larval production vary among species. Larval production and settling studies were conducted for three species of freshwater plumatellid bryozoa: Hyalinella punctata (Hancock), Plumatella repens L., and Plumatella emarginata Allman. All three species were collected from two artificial lakes in southwestern Ohio. Hyalinella colonies released larvae for 5-6 weeks from early July to late August. Larval production in Plumatella repens occurred throughout June. Plumatella emarginata produced larvae in late summer (August and September) with peak production occurring in the middle of that period. Settling behavior studies were conducted with larvae of Hyalinella and P. emarginata. In both species the larvae responded similarly to light and gravity, demonstrating no phototaxis and a negative geotaxis. Settlement was significantly increased on substrates that had been aged in lake water for at least 24 hours. Hyalinella larvae in general demonstrated a settling preference for substrates of particle sizes larger than 0.5 mm. diameter. THE DISTRIBUTION OF CRAYFISH SPECIES IN THE TWO STREAM SYSTEMS 10:15 OF AN ANCIENT VALLEY IN SOUTHWESTERN OHIO F. Lee St. John, The Ohio State University, Newark, OH 43055 The crayfish populations of a valley running from Middletown in Butler County to near Hageman in Warren County, Ohio, were studied. The valley, which was once apparently part of the Teays system, is now occupied by two small stream systems, one flowing northwest into the Great Miami River and the other flowing southeast into the Little Miami River. The two stream systems were once connected a± their headwaters by a swamp. Five species of crayfish, Orconectes rusticus, O_. sloanii, Cambarus d. diogenes, C_. ortmanni and c. sp. (ref. see laevis)were found in the valley. In the northern, industrialized part, only (O. rusticus is present. Proceeding southeast in the valley species diversity increases. Moreover, the greatest diversity occurs at the edge of the valley. Four of the crayfish species are found in both the northwest and southeast stream systems in the valley. How- ever, O_. sloanii is found only in the northwestern flowing system. COURTSHIP BEHAVIOR AND REPRODUCTIVE ISOLATION IN A SPECIES OF WOLF SPIDER Gail Stratton and George Uetz, Dept. of Biological Sciences, University of Cincinnati, Cincinnati, Ohio 4.5221 Studies of a new spider species, Schizocosa rovneri Uetz and Dondale, provide an example of how sexual communication functions as a species isolating mechanism. Courtship behavior in this species is distinct from that of Schizocosa ocreata (Hentz), a sibling species with identical genetalia. Sexual communication between males and females is the critical factor in the reproductive isolation of these species. Communication through substratum-coupled stridulation plays a major role. Courtship behavior of males of both species is described from a film presentation. The auditory communication was recorded by use of a high sensitivity accelerometer vibration pick- up attached to a pre-amplifier, a sound level meter and a tape recorder. Sonograms of these tapes are presented. A series of experiments was designed to isolate the various components of sexual communication in S. rovneri (visual, olfactory, tactile and auditory). For the male, olfactory and/or tactile cues from the females silk is sufficient to release courtship. Visual stimuli is also sufficient if the female moves. For the female, auditory communication (stridulation of the male palps) is necessary and sufficient to induce receptive behavior. A forced mating technique using anestization of the female spider allows a test of inter- fertility. Heterospecific pairings resulted in eggsacs and offspring. It is suggested that differences in courtship behavior serve- to maintain reproductive isolation in these two species. ZOOLOGY A. ZOOLOGY AFTERNOON SESSION Bareis Hall B4 ANDREW WHITE, Presiding 1:30 Business Meeting ENZYME CHANGES ASSOCIATED WITH HEPATIC GLYCOGEN METABOLISM IN HYPOPHYSECTOMIZED 2:00 GOLDFISH. Ralph Paxton and Bruce L. Umminger. Dept. of Biological Sciences, University of Cincinnati, Cincinnati, Ohio 45221 Hypophysectomy of 20 C-acclimated Carassius auratus results in accumulation of hepatic glycogen (172 mg/g of liver) when compared to intact fish (93 mg/g of liver). Total hepatic glycogen synthase activity remains unchanged, while the % of glycogen synthase in the active form is increased in the hypect fish (6.5%) compared to the intact fish (1.2%) . Total hepatic glycogen phosphorylase activity and the % in the active form is decreased in the hypect fish (2.62 umoles PO4/10 min/mg of protein, 74.4%, respectively) in comparison with the intact fish (4.57 umoles PO^/lOmin/mg of protein, 83.1%, respectively). The activities of hepatic hexokinase, glucose-6-phosphatase, fructose diphosphatase and and pyruvate kinase remain unchanged, while hepatic glucose-6-phosphate dehydrogenase and phosphofructokinase are both depressed in the hypect fish. Hepatic glycogen accumulation in hypect fish is accompanied by increased glycogenesis, decreased glycogenolysis, decreased pentose phosphate shunt, and decreased glycolysis (as measured by either an increase or decrease in the activity of the regulatory enzyme associated with that particular pathway). The activities of the following muscle enzymes remain unchanged with hypophysectomy: hexokinase, glucose-6-phosphate dehydrogenase, phosphofructokinase, and pyruvate kinase. The activity of fructose diphosphatase is decreased in the hypect fish when compared to the intact fish. PARASITES OF THE BRINDLED MADTOM,NOTURUS MIURUS (JORDAN) IN CENTRAL OHIO. o.-ig Bowen, Charles A. and Crites, John L. U.S. Environmental Protection Agency, 401 M St. SW, Washington, D.C. (TS-769), 20460 and The Ohio State University, Zoology Bldg., 1735 NeilAve., Columbus, Ohio, 43210. Three hundred and forty four Brindled madtoms (Noturus miurus) were collected from Salt Creek.Ohio, over a two year period (Oct. 1974 - Sept. 1975; April 1977 - July 1977). The majority (234) of the specimens autopsied were preserved in individual bottles containing a buffered solution of 10% formalin at the time of collection. The remaining 68 madtoms consisted of freshly posted specimens. Parasites collected included one species of monogenetic trematode, two species of digenetic trematodes, one species of cestode, two species of nematodes, one species of hirudinea, and one species of branchiura. Of the eight species recovered seven represent new host records. With the exception of the parasitic cestode, the incidence of parasitic infection was low with only 8% of the madtoms surveyed being parasitized. Cestodes recovered were primarily in the form of encapsulated plerocercoid larvae that infected 89.57o (males = 89.9% and females = 90.0%) of the population. The mean worm burden values were 35.19. (range 18-76) and 28.1 (range 1-59) for male and females respectively. ZOOLOGY OBSERVATIONS ON RAT POPULATIONS IN THE NORTHERN MARSHALL ISLANDS. Manfred Temme 2:30 and William B. Jackson. Environmental Studies Center, Bowling Green State