1917] Cockerell—New Social Bees 120 
more miscellaneous variation in Bombus, and less tendency to 
produce a series of slightly different yet constant races. 
Although we cannot discern any obvious connection, at least of 
an adaptive nature, between the color-variations of all these genera 
and the environment, it does not follow that no relation of any 
sort exists. In Bombus, at least, there are some very remarkable 
cases of parallel variation in particular regions. This subject has 
been dealt with at length by Friese and Wagner, and O. Vogt, and 
Sladen gives a summary of some of the more important facts in 
his work ‘The Humble-Bee,” p. 148. A most striking case is 
described below; the beautiful black, white and red colors of 
Bombus terrestris simlaénsis are duplicated by those of B. niveatus 
callophenax from the same region, though structurally the bees 
are quite distinct. It is beyond belief that all these cases of 
parallel color variation are accidental, depending on no common 
cause. There may be Miillerian mimicry involved, but the. whole 
subject appears to need further investigation. It is not impos- 
sible that in some cases the coloration really indicates relation- 
ship, and that the structural characters have varied. We always 
tend to assume that structure is far more permanent than color or 
marking, but fossil insects show the enormous antiquity of color- 
patterns. In the quite numerous cases in which bees resemble in 
color and pattern species of quite other genera, or even wasps, 
it is manifest that the colorational similarity is secondary, and 
not due to common descent from insects so colored. 
Bombus terrestris simlaensis Friese 
Female: Kashmir, 9,000 ft., June 1911 (R. L. Woglum). This 
has the relatively short malar space of B. terrestris, as also has a 
worker of B. terrestris fulvocinctus Friese, from Simla, which was 
labelled B. tunicatus Smith in F. Smith’s collection. Meade- 
Waldo has recently referred B. tunicatus Smith as a variety to B. 
lapidarius; but the specimen before me, from Smith’s collection, 
has rather the structure of terrestris. The type locality of tuni- 
catus is Chusan, China. According to Meade-Waldo, B. gilgitensis 
Cockerell is also a variety of B. lapidarius, but the form of the malar 
space seems to ally it rather with B. terrestris. Bombus incertus 
Morawitz, which I have from A. Skorikov, is said by Meade-Waldo 
to be the same as tunicatus; tt has the structure of lapidarius, not 
