Proceedings of the Helminthological Society of Washington

STEIN, PAUL C., AND RICHARD D. LUMSDEN.   The Ultrastructure of Developing Metacercarial Cysts of Ascocotyle leighi Burton, 1956 (Heterophyidae) ……1

LEE, CLARENCE MATTHEWS, AND DAVID RICHARD LINCICOME.   Trypanosoma duttoni: Cell Populations and Antibody Formation in Pantothenate-deficient Mice ……11

NAIR, PANKAJAM, AND A. COOMANS.   Anchobelondira clavicaua gen. n., sp. n. (Nematoda, Belondiridae) from South Africa ……16

NASIR, PIR, AND MARCOS T. DIAZ.   Studies on Freshwater Larval Trematodes. XXVII. Partial Life Cycle of Caiguiria anterouteria gen. n., sp. n., subfam. n. (Trematoda: Digenea) ……21

BECKER, C. DALE.   Cestrahelmins rivularis sp. n. (Digenea: Deropristiidae) from White Sturgeon, Acipenser transmontanus, in the Colombia River, Washington …..23

LINDAHL, I.L., M.L. COLGLAZIER, M.L. CRANDALL, AND R. L. WILSON.    Effect of Management systems on the Growth of Lambs and Development of Internal Parasitism. V. Field Trials Comparing Early Weaning Versus Late Weaning and Involving Medication with Thiabendazole and Purified Micronized Phenothiazine ……27

SULLIVAN, JAMES J.   Pseudosonsinotrema echinophallus sp. n. (Digenea: Pleurogenidae), a New Trematode from Rana pipiens Schreber in Costa Rica ……34

CHRISTIAN, FREDERICK A.   Pseudosonsinotrema catesbeianae sp. n. (Trematoda: Pleurogenidae), from the Bullfrog, Rana catesbeiana Shaw ……37

CIORIA, H., AND H.C. MCCAMPBELL.   Anthelmintic Efficacy of Four dose Levels of Cambendazole in Cattle ……40

TIMM, R.W. Antarctic Soil and Freshwater Nematodes from the McMurdo Sound Region ……42

WILSON, G.I., AND K.S. SAMSON.   The Incidence of Fascioliasis of Sheep and Cattle in the Southwest with Observations on the Snail Vectors ……52

BRUCE, J.I., M.D. RUFF, J.E. WILLIAMS, P. TORTI, AND G. SIKKEMA.   Comparative Respiration of the Life Cycle Stages of Paragonimus ohirai, Miyazaki, 1939 ……56

WEBSTER, W.A.  Geopetitia aspiculata sp. n. (Spirurida) from Coerulea coerulea and Other Imported Birds in the National Zoological Park, Washington, D.C. ……64

TURCO, C.P., WALTER H. THAMES, JR., AND S.H. HOPKINS.    On the Taxonomic status and Comparative Morphology of Species of the Genus Neoaplectana Steiner (Neoaplectanidae: Nematoda) ……68

MAGGENTI, A.R.   A Review of the Family Cucullaidae Cobbold, 1864 and the Genus Bulbodacnitis Lane, 1916 with a Descroption of Bulbodacnitis ampullastoma sp. n. (Nematoda: Cucullanidae) from Salmo gairdnerii Richardson ……80

OLSEN, O. WILFORD, AND CLAIT E. BRAUN.   Diplotriaena lagopusi and D. andersoni spp. n. (Diplotriaenidae: Filarioidea) from White- tailed Ptarmigan (Lagopus leucurus) in North America ……86

THORNE, GERALD, AND JAMES D. SMOLIK.   The Identity of Paratylenchus nanus Cobb, 1923 ……90

WERTHEM, GUTA, AND Z. GREENBERG.   Helminths of Mammals and Birds from Israel. II. Sinaiotaenia witenbergi gen. et sp. n. (Cestoda: anoplocephalidae) from Desert Rodents ……93

BUSCHER, HENRY N., AND A. JAMES HALEY.   Intestinal Helminths of Rattus rattus from Urban and Rural Areas in the Punjab Region of West Pakistan ……96

POINAR, GEORGE O., JR.   Rhabditis adenobia sp. n. (Nematoda: Rhabditidae) from the Colleterial Glands of Oryctes monoceros L. and other Tropical Dynastid Beetlse (Coleoptera: Scarabaeidae) ……99

THATCHER, VERNON E.   Some Hookworms of the Genus Ancylostoma from Colombia and Panama ……109  

JOLLEY, WILLIAM R., DATUS M. HAMMOND, AND MERTHYR L. MINER.   Amprolium Treatment of Six – to Twelve-month-old Calves Experimentally infected with Coccidia ……117

VEGORS, H.H., AND JOHN T. LUCKER.   Age and Susceptibility of Cattle to Initial Infection with Cysticercus bovis ……122

RESEARCH NOTES