246 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
life history of the insect. The wing and tibial colors differ much, 
not only specifically but also individually in the same species, 
frequently varying, on the tibiae, from clear yellow to red, some- 
times deeply infuscated, or from red through yellow and greenish 
to deep blue ; on the wings from pinkish red to yellow and j^ellow- 
ish white. From numerous observations a blue color of the wings 
and hind tibiae seems to be associated with a certain degree of 
aridity of climate, a red color with humidity. Probably addi- 
tional factors are involved. 
Since all Locusts are single-brooded in New England there is 
not the opportunity to develop seasonal phases of coloration, 
such as frequently occur in butterflies. The nearest approach to 
anything of the sort is the gradual deepening of tint which takes 
place during life. This is shown well in old individuals of the 
Green-striped Locust taken late in the season, particularly of the 
brown phase, the paler brown tints of the spring having become 
much darker, even nearly fuscous in places. This effect is 
doubtless due to a gradual development or deposit of pigment in 
the cuticular layer with long exposure to light, a phenomenon of 
age rather than of season. There is probably also a difference of 
tint in the wings of the Sand Locust during the life of the individ- 
ual due to a similar increase of yellow or red pigment, but this 
needs to be investigated. The effect of exposure to low tempera- 
ture might be called a seasonal phase of coloration. It is shown 
by Melanoplus luridus and M. femur-ruhrum after several heavy 
frosts late in the fall; examples taken then exhibit a general 
duskiness of coloring decidedly at variance with the clear yellow 
and green tints seen early in the season. 
Though individuals of certain species vary enormously in 
depth of hue, few examples of true albinism or melanism are 
known ; the most striking one which I ever saw was a melanistic 
example of Paroxya davuliger in which the usual clear yellow 
and olive tints were supplanted by a greenish black with an 
oily lustre. "White" Crickets and Cockroaches are of course 
simply recently molted individuals. Black specimens of the 
Swamp Locust {Paroxya davuliger) have been captured, and a 
black form of the Differential Locust {Melanoplus differentialis) 
is locally common in the West. In the South the Lubber Grass- 
hopper {Rhomalea) is represented in part of its range by a form 
almost wholly deep black. 
