piisbby: ok metostbacojt, x.m.v. 2o 



irregular, the larger polygonal meshes subdivided by a superficial 

 network. The mantle is large, free for only a short distance in front, 

 the lateral edges barely free, posterior margin considerably 

 hanging, h completely encloses the shell. The breathing pore is 

 Behind the middle of the right margin of the mantle ; the genital 

 aperture close behind the right tentacle. 



Shixl (PI. Ill, Figs. 5, 6) not -pirn], thin, shaped like that of 

 Ai'iy-i'i, auct. ( = Tethys, Linn., loth ed., and Pilsbry); oblong 

 somewhat convex, posterior margin obliquely truncated; apex slightly 

 incurved, forming a very small beak-cavity ; exterior s 

 with a thin, straw- tinted cuticle, sculptured with lino, deep, and 

 ii ;■ gular g] owth-wrinkles. 



Ikteenal A.wiomv. — Body-cavity ting the tail for a short 



distance [indicated by a dotted line in PI. 111. Fig. 1, ; the stomach and 

 beginning of the intestine '•/■ /; and the main mass of the genitalia, 

 lying in the cavity of the foot ; the other folds of the intestine, the 

 tis, and the pallial organs lying in the cavity of the mantle 

 or • hump.' 



Jaw Tl. Ill, Fig. '■> arched, with eight strong ribs, the ends smooth. 



Radula with teeth of helicine form, the centrals having subobsolete 

 side cusps, and a small projection on the anterior edge of the basal 

 Laterals with the entocones suppressed. Marginals tricuspid, 

 the entocone and mesocone united I'l. ill. Fig. 10). 



Intestinal tract. — Buccal mass short and - Salivary 



glands raggedlj s Crop and stomach not sep 



forming a. long, wide passage which lie9 ventrally in the body-cavity; 

 second fold of the gut passing forward and upward, penetrating the 

 Ever; third fold lying imbedded in tl e of the liver; 



fourth fold transverse to the body, becoming free from the liver near 

 it- termination. 



/.'-/•' (I'l. nr, Fig. 4, L.) short and compact, crowded into the 

 dorsal cavity against the kidney. 



Genitalia. — Atrium extremely short. Peru'- lone, longitudinally 

 many ridged inside, with an encircling swelling at its termination, 

 where there i- a fleshy partition or valve [scarcely a papilla) within; 

 epiphallus as wide as the penis, short, bearing the retractor muscle; 

 flag< Hum rapidly tapering and shorter than the epiphallus ; vas- 

 deferens slender, free. The dart-sac i- inserted on the atrium, is 

 ovate, v«-ry large in proportion to the other organs, and bears near its 

 distal end two large, distorted, club-shaped mucous glands. These 

 glands show branching white vein- and are thin-walled distallj 

 each one contain- a stout, fleshy terminal papilla. The walls of the 

 thick and of the usual muscular tissue, but in the single 

 specimen dissected there was no dart in the lumen. A few muscle 

 connect the apex of the dart-sac with the lower end of the 

 uterus, exactly as in the genus Cepolis. In fact, the whole dart 

 apparatus is strikingly like that of Cepolis} J b< gina is long, over 



1 Cf. Man. Conch., ser. n, vol. ix, pi. lii, figs. 12, 14, and 10. 



