108 MOLLUSCA. 
Very similar to the next species, but smaller and less ventricose, 
smoother and horn-coloured, and with one whorl less, and moreover 
the umbilicus is margined by a rib. It is smaller than C. ¢terebrale. 
It is possibly the C. dubium of Pfeiffer, though he describes the peri- 
stome as interrupted. 
Figure 122, front view of the shell, enlarged ; 122 a, natural size. 
CycLosToMA scITuLUM (Gould). 
Testa parva, elongato-conica, tenuis, rufo-cornea, strits incrementi tenui- 
bus solum insculpta, arcté umbilicata: spira elevata ; anfractibus sex 
vel septem rotundatis, supernis sub-angulatis ; sutura profunda : aper- 
tura rotundato-ovata, parva, trientem longitudinis adequans ; peristo- 
mate simplict, pallido. 
Cyclostoma scitulum, Gouin ; Proceed. Boston Soc. Nat. Hist., ii. 
206. March 1847. Expedition Shells, 39. 
SHELL minute, thin, elongated, ovate, covered with a delicate red- 
dish horn-coloured epidermis, exhibiting faint and irregular lines of 
increment of a paler colour. Spire elevated, of nearly seven rounded 
whorls, separated by a deep suture, the upper ones somewhat angular 
posteriorly ; aperture small, rounded-ovate, about one-third the length 
of the shell. Lip simple, pale, united with the penultimate whorl on 
the columellar side for a considerable space. Umbilicus elongated, 
very small. 
Length one-fifth of an inch; breadth exceeding one-tenth of an 
inch. 
Found at the islands of Tahiti, Eimeo, and Manua. Couthouy. 
Almost exactly like Amnicola Sayana, Anth. It is larger and more 
ventricose than C. vallatum, and is distinguished from C. terebrale by 
its less slender form and unexpanded lip. 
Figures 123, and 123a, two views of the shell, enlarged; 123 4, 
natural size. 

