102 PARTULINA, SECTION BALDWINIA. 



be impossible to determine with any degree of certainty the 

 parentage of the greater number of embryonic shells of this 

 species from their appearance alone whether they came from, 

 banded, multi-banded, or unicolored shells. Clearly the color 

 varieties are not yet fully established. 



" It is well known that many of the species of the Achati- 

 nellidce are indifferently dextral or sinistral. Some, how- 

 ever, are consistently one or the other, and the P. confusa be- 

 longs in the latter class. Among upwards of ten thousand 

 individuals of confusa examined, not a single dextral shell 

 was found. 



' ' Most of the Achatinellidtf proper, as is well-known, dwell 

 upon trees and the greater number of individuals of the 

 several species pass most of their time upon the leaves, feed- 

 ing and moving about only by night and, to a very limited 

 extent, on dark and rainy days. A certain amount of) 

 moisture apparently the more the better seems indeed nec- 

 essary to their mode of progression, if not to their very exist- 

 ence, and in dry weather they are strictly sedentary. 



' ' The three species in question dwell indifferently upon the 

 trunk, the branches, and the leaves of trees, though in day 

 time the greater number are attached to leaves. As a rule 

 they appear to be very sluggish and often remain for weeks, 

 especially when young, attached to leaves and branches with- 

 out moving and apparently without eating. Individuals in 

 captivity have been known to live a couple of months without 

 food or water, which argues the possession of considerable 

 vitality. Under such circumstances adult shells are known 

 often to give birth to apparently healthy young. 



' ' Unlike the Arnastras and the Succineas, the Acha,tmelUd& 

 proper do not appear to feed upon the chlorophyl of 

 leaves; at least the leaves upon which the shells are found 

 seem never to show visible signs of their work. The two 

 former groups consume leaf tissue voraciously, both dead 

 and living foliage, and often leave them completely skeleton- 

 ized. Both of these groups live also no doubt to a considerable 

 extent on fungi, as they are often found upon dead wood. 

 Indeed the presence of Succinea in numbers upon coffee trees, 



