UROCOPTIS. 107 



being cylindrus, which was selected as type of the group 

 by Gray in 1847. Probably all of the species cited by Beck 

 belong to the group of large typical forms, except the last, 

 gracilicollis, which is a Brachypodella. Only two of Pfeif- 

 fer's original list of Cylindrella belong to the genus Urocoptis 

 as now understood, five preceding them falling in Brachy- 

 podella, and one following is a Clausilia. The subgenus 

 Cochlodina of Ferussac contained several species of Urocoptis, 

 together with many species of Clausilia and other genera ; but 

 his diagnosis agrees only with Clausilia. The standing of 

 Urocoptis as the generic name for the present group seems 

 therefore secure. 



Two species, U. scccva and U. coronadoi, are sinistral. All 

 the rest are dextral. 



Soft Anatomy of Urocoptis. 



The foot (in U. brevis from Milk River, Clarendon, Ja- 

 maica, and U. poeyana, Miami, Florida) is very short; upper 

 surface irregularly granose, without pedal grooves or a dis- 

 tinct margin ; sole not divided longitudinally, finely wrinkled 

 transversely in alcoholic preparations of U. poeyana, irregu- 

 larly and coarsely so in U. brevis. The mantle has small 

 right and left neck-processes near the pneumostome. 



The genitalia (pi. 27, fig. 44, U. brevis x 5). Atrium very 

 short. Penis (p.) very stout, without special retractor mus- 

 cle, the apex being attached to the right ocular muscle. There 

 is an ample vagina, the spermatheca (sp.) being small and 

 ovate, on a very long duct (d. sp.) . The uterus is long, 

 ample, and sacculate as usual. The ovo-testis is imbedded in 

 the lower lobe of the liver, and is lodged near the base of the 

 conic portion of the shell. 



The free retractor muscles (pi. 27, fig. 44, U. brevis x 5). 

 The right ocular retractor (r. o.) is united for some distance 

 with the columellar muscle (tail and mantle retractor, c.). 

 The left ocular band (I. o.) and the pharyngeal retractor are 

 free to their common insertion with the columellar muscle, on 

 the axis of the shell in about the fourth whorl. The apex of 

 the penis is attached to the right ocular band, which thus 

 functions also as a penial retractor muscle. 



