SCHLOSSBERGER, ON CRYSTALS IN CATERPILLARS. 35 
ganic matter; not unfrequently, also, they are distinguished 
from mineral calc-spar by their curved surfaces. 
Whether the crystals in the Malpighian vessels of the 
caterpillar of Sphinx convolvuli, described by H. Meckel 
(Mull. ‘ Arch.,’ 1846, p. 44), and those noticed by Leydig in 
the renal canals of Bombyx rubi and Talus (Mull. ‘ Arch.,’ 
1845, p. 466), are chemically identical with those above 
noticed, cannot be determined, since neither author has com- 
municated any chemical details. The former describes the 
crystals in Sphynx convolvuli as quadrate pyramids, sometimes 
white, and sometimes constituted of two white and an inter- 
mediate red layer. The crystals noticed by Leydig were 
octahedrous, whence it is very probable that these also con- 
sisted of oxalate of lime. 
