462 NEW YORK STATE MUSEUM 



bodies of water. Prof. Herrick of the Agricultural college of Mississippi 

 found it transforming abundantly on the shore of Canandaigua lake at 

 the natural science camp in June 1897. I have found it at Ithaca and 

 at Saranac Inn; at the latter place only in Little Clear pond, near the 

 oudet. That was during the week which included June 30. The 

 nymphs were crawling up out of rather deep water on stumps and logs 

 on the bank to transform. 



A big pine stump that stood partly in the water, halfway between the 

 outlet and the cold water pipe, seemed a favorite place of transformation. 

 It was fairly dotted over with exuviae, most of which were several feet 

 above the water. No imagos were seen, excepting the few that were 

 bred. 



Nymph. (PI. 18, fig. i) Total length ^^ mm; abdomen 22 mm; 

 hind femur 7 mm ; width of head 6 mm, of abdomen 7 mm. 



Body elongate, little depressed, little hairy; color dirty brownish, 

 becoming clear brown on the apex of the abdomen ; some darker mark- 

 ings on the sides of the thorax and at the lateral margins of the abdo- 

 men, and across the base of the dorsum of the middle abdominal 

 segments. 



Head cordate in outline, the hind margin being broadly emarginate ; 

 antennae long, considerably surpassing the tip of the labrum, and 

 upturned beyond the end of it; first segment twice as large as the second, 

 both globular; third segment narrowly cylindric, more than twice as long 

 as the two basal ones together, bearing the minute, rudimentary, 

 globular, fourth segment on its upturned tip; burrowing hooks well 

 developed. 



Abdomen narrowed beyond the sixth segment rather regularly ; dorsal 

 hook on segments 2-9 regularly increasing in size and sharpness, and 

 regularly increasingly declined posteriorly, that on segment 9 being a 

 direct continuation of the sharp middorsal ridge of the segment, black 

 tipped, lateral spines on segments 6-9 increasing in size posteriorly, those 

 of the ninth segment reaching the level of the middle of the loth seg- 

 ment; the eighth segment is a third longer than the loth; the ninth 

 segment is two and one half times as long as the loth; the superior and 

 inferior appendages are somewhat longer than the loth segment, but the 

 laterals are about equal to it, being about one fourth shorter than the 

 other appendages. 



The mentum of the labium is rather regularly widened anteriorly, with 

 a straight front border; lateral lobes strongly arcuate, with end hook 

 distinctly more prominent than the nine or ten coarse, angulately serrate 

 teeth before it on the inner margin. 



Subfamily aeschninae^ 

 This group includes the largest, fleetest, and most voracious of our 

 dragon flies. Many of them are common and very well known. Most 

 of the species are marked with bright blues and greens. They roam far 

 from water, and often find their way into houses in warm weather. Several 

 species are commonly seen coursing over lawns in the evening twilight. 



