1907.] NATURAL SCIENCES OF PHILADELPHIA. 501 



TiOngtli 14.8-1 o.;>, (liaiii. I iniii. 



'Uw clausiliiiin (I'l. X.XXIl, figs. 6, 7) is much twisted, tapering 

 and ac'uniinatc distally, with a notch between the thick terminal 

 point and a smaller point on the palatal side, a short distance from 

 the apex. 



Koniya, Oshiina. Osunii, Types Xo. 94,.')43, A. N. S. P., from No. 

 054<? of .Mr. lliraso'.s Collection. 



This snail is nnicli like C. mima Pils., also of Oshima, but it is 

 slightly larger and more strongly rib-striate, the inferior lamella is 

 usually distinct ly double, the subcolumellar lamella is less dilated below 

 the lower palatal ])lica, and finally the shape of the clausilium is very 

 different, as may be seen by comparing the figures here given with 

 figs. 17, 18 of Plate 22 of these Proceedings for 1901. C. koniyaensis 

 also resembles C. tokunoshimana, but differs in the shape of the clausi- 

 lium, the less coarse sculpture, more lateral lunella, etc. 



Zaptyciioid phylum. 



Numerous new species and groups of this phylum were discussed in 

 the preceding paper of this series, but the modifications of internal 

 armature and clausilium seem to be interminable, and a number of 

 peculiar additional forms must now^ be described. These require an 

 amplification and various modifications of the key to sections previously 

 given. The key given below is designed to show the natural relation- 

 ships of the groups so far as they are now understood. 



Key to the Sections of Zaptychoid Clausili^. 



I. — Lunella normally developed, lateral, oblique, above united with 



or contiguous to the upper palatal plica, which varies from 



ver)^ long to short or even wanting, but when present this 



plica projects inward ])eyond the upper end of the lunella. 



Clausilium entire and rounded distally, or rarely nuicronate. 



a. — Inferior lamella receding, inconspicuous or invisible from in 



front, obliquely ascending and straightened within the 



back of the last whorl. Remote from the superior lamella. 



h. — Shell without sutural plica?, fulcrum or parallel lamella. 



c. — Clausilium parallel-sided, flattened, rounded at the end. 



Section Hemizaptyx. 

 c'. — Clausilium swollen and callous outside near the palatal 

 margin, either angular or rounded at the end. 



Section II eterozaptyx. 

 /('.— Shell thin; sutiu'al plica^, fulcrum and parallel lamella 

 developed. Distal end of the clausilium rounded. 



Section Zaptyx. 



