3 
The collections we have studied have convinced us that every vari- 
ation may be found connecting some so-called eastern and western species, 
such as Anoplodera tibialis Lee. and A. hirtella Lee., and Anoplodera can- 
adensis Fab. and A , cribripennis Lee. Certain of these species are found 
generally throughout the Canadian and part of the Transitional Zones; 
Anoplodera canadensis Fab., A. tibialis Lee., A, sanguinea Lee., and A. 
sexmaculata Linn, are examples. 
Some species vary in size to such an astounding degree that the 
extremes are hardly recognizable as conspecific, whereas others, such as 
Grammoptera molybdiea Lee. and Anoplodera sexspilota Lee., appear to be 
rather constant in size. 
The Sternum 
The prosternum presents two apparently distinct conditions, by means 
of which the tribe may be divided into two groups. The first section of 
the tribe, from Pyrotrichus to Pidonia, has the prosternum depressed or 
concave in front of the coxae, and, in particular, transversely impressed 
or excavated by a broad, submedian groove, situated well behind the 
anterior margin; this groove being the continuation, without any inter- 
ruption on the sides, of the broad, anterior, dorsal impression of the pro- 
notum. in the genera from Grammoptera onward, the anterior, dorsal, 
transverse impression of the pronotum is interrupted on the sides by an 
elongate, oblique elevation and is not continued directly to the ventral 
side, except as a narrow sulcus immediately behind the anterior margin. 
The prosternum, therefore, appears convex, usually sloping gradually or 
arcuately from the cox® to the narrow, anterior, marginal sulcus just 
described. In Stenocorus t the intercoxal piece of the prosternum is enor- 
mously protuberant, in some males projecting beyond the coxae and formed 
into a spine. In species of Anthophilax this condition is approximated 
and in other genera a tendency toward a similar condition may be noted. 
The width of the anterior coxal separation varies considerably, even 
between species otherwise closely related. When the intercoxal piece is 
not widened at its posterior extremity, the forecoxal cavities are open 
behind, as is notably the case throughout the first part of the tribe from 
Pyrotrichus to Pidonia and in the genera Grammoptera and Alosterna. In 
some cases the intercoxal piece is reduced to an exceedingly thin septum 
which does not even attain the posterior margin of the coxse. In the genera 
which follow Pidonia in the series, the extremity of the intercoxal piece is 
variably widened, so that the coxal cavities become narrowly open behind 
and, in a few cases, such as Pseudostrangalia and Anoplodera valida Lee., 
a complete closure of the cavities is effected by the lateral projection 
of the extremity of the intercoxal piece meeting the mesal projection of the 
proepisternum behind the coxse. In Anoplodera aspera Lee. and A. muta- 
bilis Newm. the coxse are rather widely separated, suggesting with other 
characters, such as the shape of the pronotum, the feebly convex prosternum 
and the pubescent sole of the first segment of the hind tarsi, affinities with 
the first group of the subfamily. In A, biforis Newm., also, the forecox® 
are distinctly separated, emphasing the isolated position of that species. 
The mesosternum varies in width and in conformation, being usually 
oblique between the cox®, but occasionally declivous and transversely 
carinate. 
