AQUATIC INSECTS IN THE ADIRONDACKS 519 



points at the ends of the stigma as in the male, but they are more flaves- 

 cent in their basal half. The vulvar lamina is very short, being very 

 much broader than long, with a quadrangular excavation in the middle 

 separating its two low lobes widely; far beyond the apices of these two 

 lobes and near the middle of the venter of the ninth segment there is a 

 pair of minute, erect quadrangular prominences ; the apical margin of 

 the venter of the ninth segment is very convex. 



I observe in my specimens considerable variation in the size of the 

 males : 32 to 37 mm in length; the genitaha, however, are quite constant 

 in form and agree well with the figures by Hagen cited above. 



Nymph. (PL lo, fig. i, 2) Total length 18 mm; abdomen 10 mm; 

 hind femur 5.5 mm; width of head 5.5 mm, of abdomen 6.7 mm. 



Unfortunately, I obtained but few nymphs, and reared them all, so 

 that I have nothing left but the cast skins for description; these do not 

 preserve well the nymphal color pattern when dry ; there is enough of it 

 left to show that the coloration is similar to that of L. in tact a de- 

 scribed above, though probably not so well marked. The nymph is so 

 very similar to the preceding, it is hardly worth while to repeat the de- 

 scription in detail. The more salient points are as follows. The lateral 

 setae are 11; the mental setae about 13, of which the sixth (counting 

 from the side) is longest; the lateral spines of the eighth abdominal seg- 

 ment are a trifle longer than half the dorsal length of the ninth segment , 

 the lateral spines of the ninth segment attain to the level of the tips of 

 the inferior appendages, which are scarcely longer than the superior ap- 

 pendage. The dorsal hooks are as described above for L. in tact a; 

 excepting that the apex of the hook of the eighth segment is declined so 

 that it rests at its apex on the dorsum of the ninth segment. 



This last and most distinctive character between the two species is 

 shown by some nymphs which were collected for me by Chester Young 

 at EUenville N. Y,, May 30, 1897. These, from the Catskills, may be 

 the nymphs of L. glacial is also; but, among so many species so 

 much alike, and so few of them bred, they can not be so determined with 

 certainty as yet. 



The eggs are roundish oval, with a moderate investment of gelatin. 

 They are white at first, but turn a pale lemon yellow after a number of 

 hours. They are dropped by the female in flight in the little clear pools 

 along shore, strewn over the bottom with hemlock leaves. 



SYMPETRUM 



This large genus is represented in New York state by seven nominal 

 species, and an eighth is regional. Most of these species are exceed- 

 ingly common along marshy shores and in wet meadows. The imagos 

 travel often considerable distances from the water, and at the proper 

 season are met with on upland meadows very commonly. Because of 

 their familiar habits and their strikingly brilliant red coloration, they are 

 very well known. 



The nymphs are very like those of Leucorhinia, specially the 

 species placed first in our list; but they are (except S. corruptum) 



