1974] 
Cooper — Borens 
89 
Sauer 1966, perhaps Svensson 1966 2 ), B. hyemalis (Withycombe 
1926, Syms 1934, Steiner 1937), and B. brumalis (Cooper 1940, 
Crampton 1940). From its very onset the affair is between a “coy” 
female acting as though bent on escape, and an aggressive, though 
not necessarily persistent, male. An ardent male, when within some 
millimeters range, springs at the female, ensnaring her with his tong- 
like wings while seizing whatever he can of her extremities with one 
or both of his genital claspers (or gonostyles). If he fails to gain a 
hold, as he occasionally does, the female leaps away and is not directly 
pursued. Thereafter the male either takes a waiting stance on a 
sprig of moss, or courses about the moss, in both cases twitching his 
wings and opening and flexing his gonostyles from time to time. 3 
When chance again presents another or the same female, the male 
attempts once again to gain a firm hold of the female. 
When a mating spring has been successful, the male may have seized 
a female by a posterior femur (5 cases), a mid-tibia (2 cases), a pro- 
tarsus (1 case), or the antennae (1 case). In some other instances, 
in which only a part of the mating routine was followed, males had 
gained holds simultaneously of both a mid- and fore-tarsus, or a fore- 
tarsus and antenna, or a mid- and hind-tibia, and so on. The initial 
hold thus seems fortuitous and not limited to a particular appendage 
or to but one appendage at a time. Depending upon the particular 
grip of the gonostyles, and the appendage (s) seized, a male may 
either face opposite to the captured female (7 cases), and may even 
be chiefly behind her, or face in the same direction as his partner. 
When a female’s femur or tibia has been grasped, a male, without 
loosening or losing his hold, can generally draw his own body about 
to a position at right angles to that of the female by forcibly rotating 
her appendage, but he cannot wholly reverse the direction in which 
he faced without obtaining an entirely new hold, as he must when 
initially facing 180° away from his partner. 
Once seized, the female’s response is immediate and energetic, as 
though designed to free her from the clinging, intermittently passive, 
male. She drags the male on his back, his side, or even vertically on 
his hypopygium, over and through obstacles presented by the moss 
and debris. Occasionally the male acts to resist, splaying his legs 
outward as though a drag-anchor, or clutching at the moss, offering 
2 ? Also Svensson (1966), whose account must refer to B. westwoodi, to 
B. hyemalis, or to both. 
Terminology referring to the external male “genitalia” follows Michener 
(1944). 
