The morphology of the reproductive tracts of the Pacific Northwest pulmonates

Graduation date: 1964The morphology and taxonomic use of the reproductive\ud tracts of some of the Pacific Northwest Pulmonates were\ud studied. The snails examined were, Monadenia fidelis\ud (Gray), Vespericola columbiana (Lea), Allogona townsendiana\ud (Lea), Haplotrema sportella (Gould), and Haplotrema\ud vancouverense (Lea).\ud The length of the reproductive tracts of nine or more\ud individuals of each species were measured in millimeters\ud and these measurements were used as a quantitative means\ud for identifying each species. Each snail not only varies\ud in the length of specific structures, but also was seen to\ud differ from others by the presence or absence and the\ud position of certain structures. Some of the structures\ud used to separate the species were: The muscular collar on\ud the vagina in Haplotrema sportella and Haplotrema\ud vancouverense, along with the size and shape of the talon;\ud the presence or absence of a stimulator, verge, flagellum\ud and epiphallus in Allogona townsendiana and Vespericola\ud columbiana; and the presence of a dart, mucus gland, and\ud mucus ejector in Monadenia fidelis.\ud The use of reproductive tract data in taxonomy appears\ud to provide a more accurate means of identifying species.\ud It does not have the problems that are prevalent in shell\ud characters, nor does it require the skill necessary in\ud preparing and reading radula mounts. Combined with the\ud other taxonomic characters it probably provides a better\ud phylogenetic diagnosis of the various species