18 CONTRIBUTIONS FROM THE CHARLESTON MUusEUM 
263. Margarita bicarinata Kurtz.* ‘Fort Johnson” (Kurtz 
’60). 
264. Umbonium parvum Stimp.* (Kurtz ’60.) 
265. Cochliolepis parasitica Stimp. Very rare. Sullivan’s 
Island! Lives under the scales of a large annelid (Aphrodite). 
Family LIOTIIDAE 
266. Liotia gemma Tuomey & Holmes (tricarinata Stearns). 
Very rare. Sullivan’s Island! 
Family CYCLOSTREMATIDAE 
267. Cyclostrema zacalles n. sp. 
Shell minute, white, solid; whorls four, with rather distant strong spiral 
rounded ridges, the last one disappearing into the small deep um- 
bilicus; of these ridges there are two on the penultimate whorl, and 
seven or eight on the body whorl. Radiating sculpture of fine, 
close, sharp, somewhat oblique threads which cross the spiral ridges. 
Aperture very oblique; lip sinuous. Diam. max. about 1.6 mm. Alt. 
1.4 mm. 
This exquisite little shell bears some resemblance in general 
outline to Dr. Dall’s Cyclostrema turbinum as figured in the 
Blake Mollusca, plate 33, fig. 6. It differs greatly in the sculp- 
ture, which in that species consists of about 22 spiral cinguli on 
the body whorl, full three times as many as in zacalles; C. tur- 
binum is also a much larger shell. Our shell is apparently nearer 
to C. granulum Dall, but differs from that species also both in size 
and sculpture. Dr. Dall, to whose critical judgment specimens 
have been submitted, regards it as a new species. 
Five specimens have been collected. All were found in 1912 
in sand sifted from a sponge (Hercania campana?) picked up on 
the Isle of Palms (Long Island), near the entrance of Charleston 
Harbor, and are now in my cabinet and those of the Charleston 
Museum! and the United States National Museum. 
Superfamily ZYGOBRANCHIA 
Family FISSURELLIDAE 
268. Fissuridea alternata Say. Common. 
4 Spec. No. 15002. 
