GASTEROPODA. 121 
Found in streams near Lima, Peru. 
Figure 135, the animal with the shell. 
LIMNEA LEPIDA (Gould). 
Testa gracilis, elongato-conica, fragilis, diluté cornea, striis volventibus 
remotis et strus incrementalibus undulosis decussata: spira acumi- 
nata ; anfractibus quinque obliquis, convexiusculis : apertura magna, 
semilunaris, expansa ; plica columellari pernotabili, acuta. 
Limnea lepida, Gouin; Proceed. Boston Soc. Nat. Hist., ii. 211. 
June 1847. Expedition Shells, 41. 
SHELL very fragile, elongated, very acutely conical, sub-umbilicate, 
pale horn-colour ; whorls five, oblique, moderately convex, forming an 
acuminated spire; suture moderately impressed ; surface smooth and 
shining, lines of growth faint, and when examined by a magnifier 
they are found to be rendered somewhat zigzag, by distant, revolving 
furrows which cross them. Aperture large and expanded, nearly 
semicircular, half the length of shell; outer lip expanded ; columella 
having a very strongly marked, sharp fold, and broadly covered with 
a thin callus, which, not being closely appressed at the umbilical 
region, leaves a small chink. 
Length three-fifths of an inch; breadth one-fourth of an inch. 
Found at Lake Vancouver, Oregon. 
Most closely allied to L. pallida, Apams, but is much more delicate, 
the spire more acuminated, the aperture larger and expanded, the fold 
of the pillar more developed, and the surface well characterized, when 
closely examined, by the flexuous lines. The whorls are much more 
oblique and less convex than in L. desidiosa. 
Figures 141, 141 a, two views of the shell. 
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