1885.] Entomology. 307 
serving were not at hand, but it resembles quite closely another 
species which has been determined by Dr. Hagen as Lestes ungui- 
culata. The latter species, at another locality, was found deposit- 
ing eggs in the stems of bulrushes and cat-tails, the male accom- 
panying the female in a position similar to that in the first species 
named, The female saws a hole through the skin with her ovi- 
positor and deposits the egg in the pith. Similar localities have 
been diligently watched by the writer during the past two seasons, 
but it has not been his privilege again to see the dragon-flies go 
below the surfacc of the water. The laying of eggs in the stems 
of bulrushes is a very common sight about the marshy ponds 
and streams of Dakota. 
The different stages or positions in the process of copulation in 
the dragon-flies are very interesting and sometimes puzzling, 
but as a general rule they seem to be as follows :—at least it is so 
with the genus Lestes. First, the male seizes the female by the back 
of the head and flies some time with her in this position before 
the second stage is reached, in which the male, still holding the 
female, curves his abdomen and charges the seminal sac, then re- 
sumes the first position. The female seizes the abdomen of the 
male with her feet and brings the tip of her abdomen forward and 
receives the seminal fluid from its receptacle From the third the 
fourth is readily reached by the female withdrawing her abdomen 
and letting go with her feet or not as the case may be. In the 
species of Lestes before referred to the fourth position corresponds 
to the first. It seems not improbable that after laying a number of 
eggs the female may return to the second position and become fer- 
tilized for a second brood. The length of time which is occupied 
evidently varies considerably. In some cases I have observed, 
the males and females united during their rest at night. Another 
curious habit observed, especially in a large olive-green species 
of Æschna, is this: while flying at full speed the insect dashes 
flat upon the surface of the water in a pond and, apparently by 
the rebound, recovers its position in the air, This may serve the 
purpose of a bath, clearing the wings of dust, or possibly of par- 
asites.— ¥ E. Todd, Tabor, Ia., Fan. 10,’85. 
THE NUMBER oF ABDOMINAL SEGMENTS IN LEPIDOPTEROUS LAR- 
v#.—In connection with our examination of the caterpiller of 
