86 
Psyche 
[March 
crumbly or powdery. In periods of desiccation Boreus are found, if 
at all, with difficulty, unless a special method is used. 
The earliest that adult Boreus notoperates have been taken was 
mid-November, several days following the second snowfall of an inch 
or more, although it is likely that a snow or a soaking rain in Octo- 
ber would bring them forth to judge from laboratory emergences of 
pupae collected in mid-August. Thereafter adults have been found 
during the damp periods in all months until mid-March, when they 
become rare. Air and surface temperatures have been mild when 
adults have been collected, ranging from a low of 6.i°C to i8 .3°C, 
though in the November through March interval below freezing 
temperatures are not uncommon, mean low temperatures for these 
months ranging from — 4.2°C to 3.2°C, with absolute lows to 
— I2.2°C. 
Sex Ratio and Spanandry 
The sex ratio among adult B. notoperates from field collections, 
though slightly skewed toward an excess of males early in the season, 
of females late in the season, does not depart from equality; thus: 
I3icf d\ 150$$ (of which 32 of each sex were collected as mated 
pairs) ; chi-squared gives 0.3 > P > 0.2. Nor is there a departure 
from equality among immature stages collected in mid-August and 
early September. For 47 such larvae and pupae we have: 
29 late instar larvae and pharate pupae of which : 
19 sexed by dissection of gonads, giving: I2cfcf, 7?? J 
10 pupated, giving: 6 cf cf > 4$$ J 
18 pupae when found, of which: 7 cT cT , n?$ ; 
which gives a sex ratio of 25 cf cf : 22 $ $ , for which 0.7 > P > 0.5. 
Now Striibing (1950) has shown from extensive field and lab- 
oratory observations that males of Boreus hyemalis (L.) do not tend 
to emerge earlier than females in the autumn. They do, however, 
tend to die off somewhat earlier than females, and this has been 
claimed or inferred by others both from field and laboratory observa- 
tions ( e.g Withycombe 1922, Syms 1934, Cotton 1971; and for 
B. westw'oodi Hagen, Brauer 1855; for an undescribed species?, 
Kolenati 1847) 1 . My own observations on B. notoperates are in 
1 Striibing (1950) gives strong reason to believe that Brauer’s species is 
almost certainly B. westwoodi, and not B. hyemalis as he and others have 
thought. Furthermore, Pliginsky (1930) states that Kolenati’s specimens, 
from the glacier of Aar (Kazbek, Kaukas), no longer can be found, 
and are very likely an undescribed species. From Kolenati’s comments, 
they fall among the species with a reduced antennal joint number (~20). 
