No. 39] ODONATA OF CONNECTICUT: LIBELLULIDAE 259 



of the mentum, and also longer than the distance from the articu- 

 lation to the inner angle of the proximal segment of the palpi. 



Adult, male. — Color brown and green, brown predominating. 



Head : mouth parts, clypeus, labrum, front, vertex and occiput 

 brown, with black or dark brown hairs ; clypeus, labrum and front 

 usually paler. 



Thorax: uniform brown, with a dark greenish area cephalad of 

 the mesothoracic spiracle and a similar one caudo-ventrad of it; 

 caudal margin of prothorax bilobed, with long silken hairs ; legs 

 brown ; femora with yj black, heavy setae on the cephalo-ventral 

 angles, and only an occasional one on the caudo-ventral angles, the 

 remaining setae being weaker and brown in color ; tarsal claws 

 with ventral teeth almost at tips ; wings uniform brown, trans- 

 parent and without darker spots (PI. xiii, Fig. 4). 



Abdomen: uniform brown. 



Female. — Head similar to that of the male ; thorax similar 

 except the wings, which are marked as in PI. xiii. Fig. 2 ; abdomen 

 also similar ; female appendages short, about one-third as long 

 as 9, and with a shallow emargination between. 



Measurements : total length of male 25, female 20 mm. ; length 

 of abdomen, male 15, female 15 mm.; length of hind wings, male 

 18-20, female 19 mm. ; width of hind wings, male 6-7, female 

 6-7 mm. 



A dimorphic species of rather common occurrence. It is one of 

 the smallest of our dragonflies (Anisoptera). 



Connecticut. — Whitneyville, 26 July, 1905 (P. L. B.) ; New Haven, 

 July, 1905 (I. B. D.), 25 July, 1905 (W. E. B.) ; West Thompson, 12 July, 

 1905 (H. L. V.) ; Guilford (Pistapaug Pond), 8 July, 1921 (P. G.). 



New England. — June 8-September 5. 



Tribe Brachydiplacini Tillyard 



Only one representative occurs in New England — Nannothetnis. 

 The nymphs are not easily separated from other tribes, but the 

 superior terminals are as long as the inferiors and the lateral spines 

 are incurved. The adults have the anterior margin of the front 

 wings broken as in PI. xii. Fig. 2, a character present in no other 

 Libellulid occurring in this region. 



Genus Nannothemis Brauer 



Nymphs. — Head with six lateral setae on the palpi, and about 

 10 on the mentum ; abdomen without dorsal hooks, the lateral 

 spines of segments 8 and 9 similar in size and much shorter than 

 either segment ; anal appendages not decurved. 



Adults. — Wings with considerably less than 10 antenodal cross- 

 veins in both wings ; stigma with parallel proximal and distal 

 margins, less than 3 times as long as wide and supported by two 



