MORSE: ORTHOPTERA OF NEW ENGLAND. 527 
in tint, and though often prettily varied, is never such as to 
make the insect conspicuous in its haunts. 
According to Hancock, who has made a special study of the 
group, they ''feed upon the vegetable mold or decomposing soil 
sometimes mixed with algae, or on the lichens, mosses, tender 
sprouting grasses, sedges, germinating seeds of plants and debris 
found in such situations. They are ravenous eaters." Morsels 
especially prized are found on the surface of variously colored clay 
soils, and they eat the rich black vegetable mold itself. 
"In the middle of May [Illinois] the first eggs are laid in the 
ground, the female accomplishing this act by making a shallow 
burrow with her ovipositor. The young larvae, hatched from this 
brood, mature by fall, passing the following winter in the adult 
state. The broods hatched in late June and July are often imma- 
ture by the time winter arrives, and we find them hibernating 
in the pupa state. The time of incubation varies w^ith the 
temperature, the early broods of Tettix [Acrydium] hatching in 23 
days, but as the days become warmer this period is shortened to 
16 days. The number of eggs of Tettix and Paratettix varies 
considerably, but there are more often 10, 13, or 16 in each burrow; 
in Tettigidea varjdng from 12 to 26" (Hancock). 
This is an exceedingl}^ difficult group of insects to study, owing 
to the fact that individual and local variations overlap geograph- 
ical and apparent!}' even specific differences. It still needs critical 
treatment by an experienced systematist based on a large amount 
of wisely collected material before correct conclusions can be 
arrived at in regard to the relation of -the various forms. Six spe- 
cies are represented in New England, and two or three additional 
forms. Of the six, three are distinguished without difficulty, rep- 
resenting three genera. The remaining three, belonging to the 
genus Acrydium {Tettix), represent as many series of forms whose 
relation to each other has yet to be determined, and whose identi- 
fication taxes the judgment of even the expert. 
Key to New Englayid Species of Acrydiinae. 
(See Plate 24.) 
A. Antennae 12- to 14-jointed. Eyes from above not encroached upon by a 
small convex portion of the crown. 
B. Median carina of pronotum high, crest-like, arched longitudinally. 
