78 BuUetin Wisconsin Natural History Society. [Vol. 5, No. 2. 
veins and stigma, and the upper surfaces of the petiole and postpetiole 
black. 
Male. Leng'th 4.3 — 4.8 mm. Closely resembling the male of cana- 
densis, but with the wings colorless at the base as in the covarietal 
female. 
Colorado: Florissant Canon, occuring at a higher level 
(8,500) than stilcinodoides and replacing this variety along the 
margins of some of the streams and meadows. 
7. Var. frigida Forel. 
According to Forel, the worker of this variety has "the head 
longitudinally rugose, also at the sides, and nearly without trans- 
versal reticulations (in the typical hrevinodis, the sides of the 
head are more reticulated). The abdomen highly polished, with 
only a few scattered erect hairs (more hairy and with slight 
scattered punctures in the typical hrevinodis.) The whole body 
less hairy than in the typical hrevinodis. Red ; the abdomen and 
the upper side of the head brown. In all other parts like the 
typical form of the subspecies. 
''Ice River Valley, British Columbia, 5,000 feet." [Edw. 
Vv'hymper] . 
A single worker from Homer, Alaska, (A. Mehner) and a 
number of workers and males from the Bay of Islands, New- 
foundland (L. P. Gratacap) in my collection agree very well 
with Forel's description. The color of the workers and the shape 
of the antennal scapes are the same as in the var. sulcinodoides. 
The sculpture is also very similar, except that the sides of the 
head are longitudinally rugose, and the petiole is coarsely longi- 
tudinally rugose in front and transversely rugose behind. 
In the male, the scapes are very short, not longer than 
the two succeeding joints together, or of the funiculus. The 
hairs on the body and legs are nearly white. Length of worker, 
4.8 — 5.3 mm ; of the male, 5.5 — 6 mm. 
The host of the typical Leptothorax enter soiii is the variety 
above described as canadensis, that of L. glacialis the var. 
suhalpina. I have been unable to detect any difTerences in the 
habits or behavior of these two host ants. The nest of the Colo- 
