188 TORNATINA. 



Known from T. infrequens (1) by the smaller size, and more irreg- 

 ular spire ; (2) by the suture, which is not channeled ; (3) by the 

 shoulder, which is sharply carinated, with the space hollowed be- 

 tween the keel and suture; (4) by the swelling of the body-whorl at 

 the base ; and (5) by the plait which runs more transversely, below 

 the body whorl, instead of obliquely, almost on it, as in T. infrequens. 

 By some of the above characters it is further distinguished from 

 T. cerealis Gld. which resembles T. infrequens much more closely 

 than this species. All the three forms begin life as a small discoidal 

 body, like a tumid Planorbis. After making about two turns of 

 this, they proceed in the regular way affixing the disk vertically, or 

 sometimes in a slanting direction at the top of the spire. The length 

 of spire in this species, which is not so rare as T. infrequens, is ex- 

 tremely variable. (Cpr.\ 



T. INCULTA Gould. PL 59, fig. 15. 



Shell minute, ivory-white, rather solid, elongate-oval, longitudin- 

 ally most minutely striated ; spire elevated ; whorls 4, squarely ter- 

 raced ; aperture about seven-eights the length of the shell, dilated 

 below; outer lip inflexed, rounded behind; columella arcuate, 

 calloused, with one fold. The spire is sometimes scarcely exserted. 

 (Gld. & Cpr.). 



Alt. 5'5, diam. 2'5 mill. 



San Diego (Gld.) ; Monterey (Gabb), California. 



Tornatina inculta Gld., GLD. & CPR., P. Z. 8. 1856, p. 203. CPR. 

 Brit. Asso. Adv. Sci. 1856, pp. 227, 313, 351 ; Moll. Western N. A. 

 p. 79. 



My figure is drawn from a beach-worn specimen collected by 

 Gabb. The upper half of the body-whorl is rather contracted, the 

 lower half swollen, and the sutures are rather deeply channelled. 



T. CEREALIS Gould. PI. 50, figs. 39, 40. 



Shell cylindrical, with very short spire, light brown. Surface 

 smooth except for curved growth-striie. Aperture long, narrow, 

 somewhat widened below, the outer lip arched forward ; columella 

 rather straight, oblique, with a spiral fold. 



Alt. 4, diam. 1-9 mill. 



San Diego, California to Vancouver Island. 



Balla (Tornatina) cerealis GLD., Bost. Journ. N. H. vi, 1852, p. 

 375 ; Otia p. 184. GLD. & CPR., P. Z. S. 1856, p. 203. CPR., Rep. 



