516 Mr. C. L. Withycombe's Notes on 



incorporated with tlie silk, but more for support than for 

 conceahnent. Now the larva rests within, the head and 

 tip of abdomen being bent ventrally. At some time the 

 jaws are broken off to short stumps (Plate XXXVIII, fig. 5), 

 and then the pupa is disclosed. This breaking of the jaws, 

 in one case observed, could not have occurred earlier than 

 one day before pupation. 



The pupa is of quite normal form; all the appendages 

 are free, though not movable until just before the escape 

 of the imago. A pair of well-developed pupal mandibles 

 are present. These are symmetrical and have each a deep 

 notch internally. Dorsally, on each of abdominal segments 

 3, 4 and 5, is a transverse ridge of strong, hooked spines, 

 IV) doubt of assistance in escaping from the cocoon. 



With a temperature averaging 70° F. the pupal stage 

 lasts from ten to twelve days. Thus one example spun up 

 1/5/22, pupated 17/5/22 and emerged 28/5/22; another 

 spiin up 5/5/22, pupated 21/5/22 and emerged 2/6/22. 

 Emergence takes jilace in morning or evening. The pupa 

 bites an irregular slit in the cocoon with its mandibles and 

 walks to the nearest support free of damp moss. The 

 pupal skin splits along the back of the thorax and the 

 imago escapes. Later, an elongated, dark brown, shiny 

 pellet of excrement is deposited, as usual. 



Pairing is most peculiar and has never, to my knowledge, 

 been observed before. Certainly Hagen (5) missed the 

 curious courtship. The main fact is that the male calls 

 and attracts the female, not vice versa. Tillyard (12) 

 mentions a single case of a male of Psychopsis attracting a 

 female, but no details are given. Otherwise I think we 

 may say that in Osmylus alone among Neuroptera has this 

 strange phenomenon been observed. 



It will be noticed that, in life, the apex of the abdomen 

 of the male is much swollen and the 8th tergite is enlarged 

 and rounded. If this tergite is carefully dissected off, one 

 may see lying just below it, on each side, a sac pigmented 

 blackish Avithin and well supplied with tracheal branches 

 (Plate XXXVIII, fig. 9, sg). These sacs open immediately 

 behind the 8tli tergite on each side and are eversible to a 

 length of about 4 mm. They are, in fact, eversible scent 

 glands. On the second day after emergence, as twilight is 

 setting in, the male crawls to a position in which it can freely 

 hang down and display the tip of its abdomen. The wings 

 are raised away from the body and the eversible glands are 



