88 
Psyche 
[March 
males to wander widely at times in search of females, or true pecu- 
liarities of the particular populations, or perhaps of the mode or 
circumstances of collecting. Strubing’s (1950) laboratory rearings 
of B. hy emails gave 40c? cf, 36?$, and Fraser’s (1943) account 
implies that his collection (in September) of pupae of B. hy emails 
consisted of 296" cf , 21 (for which 0.3 > P > 0.2). My own 
collection of larvae, pharate pupae, and pupae of B. nlvoriundus in 
August, at the same site in Hanover, N. H., at which the adults 
scored in 7 above were later collected (December to mid-April), 
gave 30 cf cf , 33 ?$ . Pupae of B. brumalis collected (from October 
to mid-November) at Princeton, N. J., likewise do not depart from 
an equality of sexes: 40 cf cf , 46 $ ? . As Striibing (1950) concluded, 
the sex ratio in Boreus appears to be close to unity for both immature 
stages and adults, as is the case for B. notoperates. The answer to 
Lestage’s (1941) question “is there spanandry in Boreus?” must be: 
“not so far as known, and perhaps not at all,” as Lestage suspected. 
Indeed, the only significant departures so far recorded are in fact 
spangynous , not spanandrous. 
Mating 
Mated pairs of B. notoperates are found chiefly on patches of damp 
moss, free of snow, from early in November to near the middle of 
March. Although Fraser (1943) claimed B. hyemalis to be cre- 
puscular, there seems to be no special time of day that is favored for 
mating by B. notoperates if the temperature is mild ; nor is light a 
requirement, for B. notoperates mates readily in the dark (in an 
incubator, at 9°C). In but one case (of 33) has a mated pair been 
found on the snow, and that mated pair had most likely fallen a foot 
or so out onto the snow from a steep, moss-covered rock-face. Cer- 
tainly the suggestion that Boreus occurs on snow because it is easier 
to find mates there is implausible; the rule seems to be that mating 
generally occurs on or in moss, where they congregate when it is 
available to the insects. 
Nine complete matings of B. notoperates have been observed, 
namely from the first attempts of the male to gain a partner to the 
completion of intromission, as well as a good many partial sequences 
from all stages in the routine. B. notoperates is without a courtship, 
just as in the three species for which the course of events of mating 
have been described, namely B. westwoodl (Brauer 1855, 1863, 
