198 CONNECTICUT GEOL. AND NAT. HIST. SURVEY [Bull 



Abdomen : green and brown ; margin of the auricles continuous 

 with a ridge which extends ventrad to apex of the genital lobes ; 

 latero-ventral carinae of 3-8, and dorsal carinae of 2-9 minutely- 

 serrate ; median transverse furrows present on segments 2-8 ; 

 terga 2-8 not meeting on the ventro-meson by .5-1 mm., the sterna 

 therefore exposed ; loth tergum with a conspicuous dorsal median 

 tooth ; superior anal appendages 7-8 mm. long, contracted at base 

 and with a blunt ventral tubercle ; distal two-thirds with a dorsal 

 carina, the tips bluntly pointed and the mesal margin of the apical 

 half densely setose ; inferior appendage half as long as the supe- 

 riors, the dorsal surface excavated, the tips with two sharp, well- 

 separated, recurved teeth ; accessory genital appendages composed 

 of two short hooks on segment i, short nodular hamules, and 

 genital lobes projecting but little below the margins of the tergum. 

 Color pattern consisting of narrow basal median and apical green 

 rings on terga 2-7 ; basal and apical rings on 8, apical ring on 9, 

 and sometimes the sides of 10 also green (dried specimens). 



Female. — Color entirely brown in specimens at hand. 



Head : caudal margin of the vertex between the compound eyes 

 with a U-shaped emargination ; wings with rounded anal angles. 



Abdomen : with terga approximate on ventro-meson of 7, not 

 usually contiguous on the remaining segments; visible part of 

 ninth sternum triangular, projecting ventrad and with a mesal 

 carina ; superior anal appendages about 7 mm. long by 2 mm. 

 broad, lanceolate, the tips broadly rounded ; ovipositor with a con- 

 spicuous carina on the lateral valves, the lateral plates visible for 

 one-third the length of 9; styli a little more than .7 mm. long. 



Measurements : total length, male 85, female 87 mm. ; length 

 of abdomen, male 57-59, female 56-58 mm. ; length of hind wings, 

 male 53-54, female 55-57 mm.; width of hind wings, male 15-16, 

 female 15-16 mm.; length of stigma, male 4.5-5, female 5.5-6 mm. 



Connecticut. — New Haven, 24 May, 1912 (H. B. K.), 28 July, 1914 

 (Q. S. L.) ; North Branford, 9 June, 1912 (B. H. W.) ; Lyme, 16 June, 

 1918 (M. P. Z.); Storrs, 1925 (A. Bulbulian). 



New England. — May 24- September. 



Family LIBELLULIDAE Rambur 



Owing to a close similarity between the Cordulinae and Libellu- 

 linae, it has been impossible to make an entirely satisfactory key 

 to the subfamilies as they stand. To overcome this difficulty, a 

 key to tribes has been constructed which, it is hoped, will enable 

 beginners to determine more accurately the systematic positions of 

 species of the larger groups. 



The family divisions given by Tillyard are listed below, together 

 with the genera occurring in this locality. The Sympetrini and 

 Leucorrhiniini have been combined because of difficulties encoun- 

 tered in separating them with the usual characters. 



