Occasional Papers of the Museum of Zoology 103 



vary greatly with the diameter. Although considerable indi- 

 vidual variation is present, the means show that C. uva knipen- 

 sis (Table XIII) quite consistently has a greater altitude for 

 the same number of whorls. The only lots of C. uva uva that 

 tend to approach them, in this particular, are the very large, 

 shells from near Landhuis Hato (Cllc, d, and C12a). 



The typical specimens (fig. xix-F5) of this subspecies come 

 from the wooded valleys of the higher hills, in the region of 

 the older rocks. These shells are very large, and have a pecul- 

 iar, porcellanous texture, which contrasts rather markedly 

 with the chalky surface of most of the shells from the lime- 

 stone outcrops. In addition, a few specimens show a slight 

 tendency to reduce the sculpture, although most of them are 

 quite as heavily sculptured as typical C. uva uva. 



C. uva knipensis (Table XIII) shows the same type of 

 ecological variation discussed in C. uva uva (Table XII). 

 Many of the animals mature with a smaller number of whorls 

 than do any of the typical subspecies. In addition, there is a 

 similar amount of variation in the major diameter. The small- 

 est specimens maj^ be called form djerimensis, new (fig. 

 xix-Al), with the top of the shore cliffs near Plaja Djerimi 

 (C17c) as the type locality. 



aBimodal: 22.4 and 25.1. 



