298 BULLETIN OF THE 



semilunar, entire, not reflected, the pillar connected with the outer lip by a 

 white callus over the body, with its boundaries sharply defined. Alt. of shell, 

 5.5; of aperture, 4.5; max. lat. of shell, 5.75 mm. 



Habitat. U. S. Fish Commission Stations 2595 and 2602, off the coast of 

 North Carolina, in 63-124 fms., sand, bottom temperature 61° to 75° P. 



This pretty little shell has a deep-water aspect, and is not sufficiently like 

 the shallow-water species to need comparison with them. According to the 

 latest catalogue of the subgenus, there is no other species known from this 



Genus GYRODES Conrad. 



Gyrodes Conrad, Journ. Acad. Nat. Sci. Phila., IV. p. 289, 1860. Stoliczka, Pal. 

 Indica, II. p. 297, 1868. Type Gyrodes crenata Conrad. 



Gyrodes depressa (Seguenza) Dall. 



Fossarus depressus Seguenza, Bull. Real. Com. Geol. I tab, 1874, fasc. ii. p. 382. 



Fossarus Crossei Weinkauff (in coll.) non Kleciak. 



Adeorbis depressus Jeffreys, P. Z. S. 1885, p. 41, pi. iv. figs. 8, 8 a. 



Habitat. Pliocene of Messina, Seguenza. Mediterranean, Jeffreys. North 

 Atlantic, 100-1360 fms., Porcupine Expedition. Off Cape Lookout, at U. S. 

 Fish Commission Stations 2612 and 2619, in 15-52 fms., sand, bottom temper- 

 ature 67°.0 F. 



This little shell is the same as that figured by Jeffreys under the name of 

 Adeorbis depressus. It has an operculum like that of Sigaretus (Fischer, Man., 

 fig. 535, p. 768). The A. fragilis of Sars has a multispiral operculum, and 

 belongs to a different family, though the shells have several features in com- 

 mon. The Fossarus Crossei Kleciak, the F. Petitiana of Tiberi, and the Sto- 

 matia azonea of Brasilia, from authentic specimens in the Jeffreys collection, 

 appear to belong to a different group and certainly to a different species. These 

 shells have every feature of Conrad's Gyrodes, except that they are smaller 

 than his type. The ridge near the suture in the type is very inconstant, and 

 often entirely absent. These shells are also somewhat variable in the com- 

 pactness with which they are wound. The nucleus is glassy, minute, globu- 

 lar, and stands up from the apex with great prominence. The shell is 

 remarkably elegant, and the largest American specimen has fully twice the 

 diameter of any of the Mediterranean specimens I have seen, though otherwise 

 indistinguishable from them. Sigaretus problematicus Deshayes (An. s. Vert. 

 Bas. Paris, III. p. 90, pi. lxiv. figs. 7-9) is doubtless a young Gyrodes, which 

 thus is carried back in Europe to the Eocene. 



