62 VARICELLA. 



perfect specimen of V. inopinata would probably be about 

 9 mm. long. 



Jamaican Species. 



Jamaica has a large number of forms still very imperfectly 

 known. Of two of them, V. gossei and V. osculans, I have 

 seen no examples. Special study must be given to the em- 

 bryonic whorls, which show varying degrees of acceleration 

 of the sculpture, the heterogeneous sculpture of the later 

 stages being sometimes carried upward upon the embryo. 



I. Intervals between the narrow ribs smooth and glossy. 



V. lioderma, no. 17. 

 II. Intervals between the ribs vertically striated. 



a. Large forms, 13 to 20 mm. long, 3 to 4 wide, with 

 9 to 10% whorls; pale brown with reddish streaks 

 or clouding. 



b. 19 to 21 narrow, irregular ribs on last whorl, 

 intervals with about 9 striae. 



V. adamsiana, no. 9. 



6 1 . 30 to 33 ribs on last whorl, 5 to 8 striae in each 

 interval; last embryonic whorl with 4 or 5 

 striae in intervals 'between riblets. 



V. chittyana, no. 11. 



Z> 2 . About 20 ribs on last whorl, intervals with 

 minute waved striae; embryonic whorls finely 

 costulate. V. davidensis, no. 10. 



a 1 . Smaller forms, 7 to 14 mm. long, less than 3 wide. 

 &. Last whorl with 12 to 14 delicate lamellar ribs, 

 higher on the shoulder, intervals with 25 to 

 40 very fine striae. 



c. 12 x 2.6 mm., 9 or 10 whorls, remotely 

 ribbed, striate between the ribs, details 

 unknown. V. gossei, no. 12. 



c 1 . Axis but slightly sinuous, no false umbili- 

 cus visible from the base. 



V. gracilior, no. 14. 



c 2 . Axis spiral, a false umbilicus visible in 

 basal view. 



