As. ddi ee ee aa 
1884.] Entomology. 825 
lives submerged in the water and attached to the under surface of 
floating leaves. Its case serves as a cocoon within which to pu- 
pate, and it is attached to some aquatic plant. The chrysalis is 
soft, with the ventral sheath prolonged to the end of the ab- 
The most curious caterpillar is that of Paraponyx, living on 
plants wholly submerged ; it is provided with gills which allow 
them to decompose the air contained in the water; and they are, 
as De Geer showed, truly amphibious, because they are provided 
at the same time with stigmata to respire ordinary air, like other 
caterpillars. 
The caterpiltar appears, at first sight, as if furnished with 
respiratory filaments of different lengths, three or four arising 
irom a common tubercle. It is the only lepidopterous larva 
known to be provided with tracheary gills. 
The chrysalis lives also wholly submerged, constructing be- 
tween the submerged leaves of the plant which nourishes it, a 
cocoon composed of a double lining of silk, wherein it changes 
into a chrysalis. The imago has to pass through the water on 
leaving its cocoon, so that it is at the beginning of its existence 
also amphibious, « 
the last genus, Hydrocampa, has caterpillars which are rather 
thick, attenuated at each end, flattened beneath, with a small 
retractile head. They live under the leaves of pond lilies in a 
aes © sac formed of two bits of leaves stuck together at their 
edges, 
The accompanying drawings, made by Dr. C. F. Gissler, un- 
abundance May 20, 1882, in its case, made from the leaves of 
ots by two lateral fleshy lobes and a posterior fleshy bead; on — 
fae Succeeding segment is a smaller cle 
the sides of the same segments. da 
e few caterpillars which I carried home began to spin 
