WATER CONTENT AND RATE OF METABOLISM 139 
males is 23.5 mm., and of females, 24.5 mm.; average weights 
are: adult males, 0.20 to 0.40 gram; females, 0.25 to 0,65 gram. 
Nymphs range in weight up to a maximum of 0.35 gram.' 
Melanoplus differentialis Uhler, the largest grasshopper found 
in this vicinity, closely parallels Melanoplus f. rubrum in life- 
history. In length adult males measure 39 mm., and females, 
41 mm. Adult males weigh 0.7 to 1.3 grams, and females, 1.3 
to 2.8 grams. 
Dichromorpha viridis Scudder has a general life-cycle similar 
to the above-described species. However, it is not as active 
an animal and occurs in open wet places. Differences in size 
between adult males and females are marked. Adult males 
measure 18.75 mm., and females,' 27.0 mm. In weight adult 
males range from 0.15 to 0.20 gram, and females, from 0.15 to 
0.55 gram. 
Chortophaga viridifasciata DeGeer is quite different in life- 
cycle from the above-mentioned species. Eggs are laid in late 
spring and early summer; these hatch in later summer and early 
fall; the nymphs live throughout the winter, and in spring grow 
rapidly, and become adults by early summer. Two-thirds of 
their active life, in contrast with other species, is spent as nymphs 
and approximately one-third as adults. Two well-marked 
varieties occur, a green form (virginaria Fab.) and a brown form 
(infuscata Harris). Most females are green and males brown, 
but some are found of each sex in either color, and as a matter 
of fact, when green animals are put at a constant temperature 
of 38°C. they turn brown in a very short time. Adult males 
measure 25 mm. and weigh 0.10 to 0.20 gram; fen\ales measure 
30 mm. and weigh 0.15 to 0.45 gram. 
For further descriptions of the above species reference is made 
to standard text-books on entomology and to the works of 
Morse (6) and Lugger (6) . 
1 Average dimensions of animals used are taken from Lugger (5), while body 
weights have been determined by the author. 
