hey 
THE NATURAL HISTORY SURVEY. 317 
Genus APLEXA Fleming, 1828. 
Shell: Sinistral, narrow, elongated, thin, polished; spire 
long; aperture narrow, long; peristome acute; columella lip 
simple. 
Anmal: With a rather long foot, rounded before and 
pointed behind; mantle not reflected over the shell and witha 
simple edge; tentacles long and slender, eyes at their bases; 
genitalia?; jaw cartilaginous, arched, brown; radula with multi- 
cuspid central tooth and comb-like lateral teeth resembling 
those of Physa. 
Distribution: Europe, North America, Northern Asia, 
Mediterranean region, West Indies, Oceanica.* 
129. Aplexa hypnorum Linné, pl. xxxii, fig. 16. 
Bulla hypnorum LINNE, Syst. Nat., p. 1185. 
Physa elongata Say, Journ. Phil. Acad., Vol. II, p. 171, 1821. 
Physa glabra DE Kay, N. Y. Moll., p. 80, pl. V. fig. 83, 1843. 
Physa elongatina LEwIS, Proc. Bost. Soc. Nat. Hist., Vol. V, pp. 122, 
298, 1855. 
Physa turrita J. DE C. Sows., Fauna..Bor. Am., Vol. III, p. 315. 
Bulinus tyront CURRIER, Amer. Journ. Conch., Vol. III, p. 112, pl. vi, 
fig. 2, 1867. (?) 
Shell: Very much elongated, thin, oblong; color yellow- 
ish-horn, with sometimes a zigzag, longitudinal band of bright 
yellow on the last whorl; apical whorls brownish, next black- 
ish and last yellowish-horn; apex broadly round; surface pol- 
ished, shining, diaphanous, growth lines numerous, but faint; 
whorls six, somewhat regularly increasing, flat-sided, convex; 
spire long, acutely conic; sutures but slightly impressed, mar- 
gined; aperture elongate-ovate, narrow, contracted above, 
somewhat rounded below and somewhat expanded, occupying 
about half the length of the entire shell; peristome thin, sharp, 
rounded, no callosity on the inside; columella narrowed near 
the base, simple; no umbilicus; a view from the base of the 
shell shows a perforation (through the aperture) from the base, 
part way to apex. 
Length, 15.00; width, 6.00; aperture length, 8.00; width, 2.75 mill. (8507.) 
ef 10.50; «4,75; 2 cs Dour a. aaa. 2th" (B506;) 
f 15.00; v7.00; WOU NT 8.50 eos (12514) 
oe 17.25; hos Cup ee - * SU CP DOr Ge 
Animal; With a rather wide foot, rounded before and 
pointed behind; head prominent, separated from the foot by a 
*Tryon, S. and S. Conch., Vol. III, p. 103.’ 
