404 Wisconsin Academy of Sciences, Arts, and Letters. 
Family LimnepMlidae 
LimnepMlus sp. 
I attempted to breed this species, but overlooked the final 
ecdysis until too late. The case is square like that of Limne- 
philus rhombicus Linne, and composed of fine bits of crossed 
twigs, fibers, etc. This species, however, is much smaller than 
its relative of the springs. 
The larva is the only active “swimmer’’ among the lake cad¬ 
dis-worms, most of which are too heavily encumbered by their 
cases to be able to swim at all (except the first and second 
instar larvae of caddis-worms which are all good swimmers.) 
The species is not infrequent in the lake. 
Platyphylax subfasciatus Say. 
This is the largest species found in the lake, although rare. 
In places it may be abundant, at a depth of about a meter. Its 
congener, P. designatus Walker, and relative, Neophylax autum- 
nus Vorhies, are quite thick in the waters of Merrill Spring. 
Family Phryganeidae. 
Phryganea interrupta Say. 
A single specimen of this species was taken in the lake, in a 
sheltered part of University Bay. Like Neuronia postica 
Walker, it is more characteristic of smaller streams and ponds, 
and is not uncommon in Pheasant Branch Creek. Here it lives 
among the roots of the plants or buried in the fine silt of the 
bottom. 
J. Order Diptera 
The Diptera have adapted themselves to a greater variety of 
conditions than any other order of insects. These conditions range 
from aerial and terrestrial to subterranean and aquatic, from 
ectoparasitic to endoparasitic. On a taxonomic basis none of 
these conditions can be stated as characteristic exclusively of the 
different groups of the order. For instance, all transitions from 
a damp habitat to a semiaquatic and holaquatic habitat may be 
found. These transitions take place within close rela¬ 
tionships, and the facility with which members of a single family 
pass from one extreme to another is extraordinary, and de- 
