20 
John R. Holsinger and David C. Culver 
Octolasium lactewn (Oerley) (TX) 
Virginia. — Bland Co.: Newberry-Bane Cave. Scott Co.: Grigsby 
Cave. 
Order Lumbriculida 
Family Lumbriculidae 
Spelaedrilus multiporus Cook (TB) 
Virginia. — Russell Co.: Smiths Cave (type locality). 
Stylodrilus ( Bythonomus ) beattiei Cook (TB) 
Virginia. — Tazewell Co.: Steeles Cave. 
Comments. — Also recorded from three caves in southern West 
Virginia (Cook 1975). 
Genus (?) species (?) 
Virginia. — Lee Co.: McClure and Spangler caves. 
Comments. — These populations represent an undescribed, troglobitic 
species (D. G. Cook, pers. comm.) 
PHYLUM MOLLUSCA 
Both aquatic and terrestrial snails (class Gastropoda) have been 
collected from caves in Virginia and eastern Tennessee, but the former 
are far more common in subterranean habitats than are the latter. Aside 
from several species of Goniobasis, which are sometimes abundant in 
karst springs and occasionally penetrate some distance into cave streams, 
aquatic cave snails of the Appalachians are members of the family 
Hydrobiidae, and most apparently belong to the genus Fontigens (Fig. 
13D). Cavernicolous hydrobiids commonly inhabit the undersides of 
flat rocks in small streams with relatively constant flow. 
Owing to the fact that the taxonomy of the cave and spring 
hydrobiids is based largely on shell morphology (see Hubricht 1976), 
which is often highly variable, identities of some of the species listed 
below are, in our opinion, questionable. There are a number of 
peculiarities that are perplexing about the geographic distribution (Fig. 
7) and ecology of these species. For example, Fontigens aldrichi has 
been recorded from caves and springs in the Ozarks and Appalachians 
and is represented in both regions by eyed, pigmented populations living 
principally in springs, and by eyeless, unpigmented populations living 
principally in caves (Hubricht 1976, Peck and Lewis 1978). Another 
species, F. orolibas, although resticted to the Appalachians, has been 
identified from eyed, pigmented populations living in springs in the Blue 
Ridge Mountains and from blind, unpigmented populations living in 
caves in karst valleys to the west (see Hubricht 1957, 1976). Similarly, 
blind, white snails from caves in the Powell Valley of southwestern 
Virginia have been tentatively assigned by Hubricht (1976) to 
