No. 39] ODONATA OF CONNECTICUT : COENAGRIONIDAE 85 



cephalic lobe, and in some specimens a small blue spot on each 

 side on the median lobes, caudal margin also blue; proepimera 

 black above, pale or blue below ; mesostigmal plates about half 

 blue. Alesothorax with a broad dorsal stripe, covering the carina 

 and also half of the mesanepisterna on either side; this is fol- 

 lowed by a blue stripe which occupies most of the remaining por- 

 tion of the anepisterna of the mesothorax ; mesopleural suture 

 covered with a black stripe which is considerably widened near 

 the caudal margin of the katepisternum and extends over that 

 sclerite covering the dorsal half or third ; remainder of the thorax 

 blue or buff ; legs black and bufif, the coxae and trochanters pale, 

 the femora with a dorsal black stripe including one row of setae ; 

 tarsi and claws black, shining; front wings with 9-1 1 postnodal 

 cross-veins, and M, arising between the fourth and sixth of these, 

 usually near the fifth. 



Abdomen : blue and black ; a basal spot on the first, a dorsal 

 apical spot and ring on the second, apical three-fourths of the dor- 

 sum of the third, dorsum of 4, all of 5 and 6 except narrow basal 

 rings and lateral margins, cephalic half of 7, and all of the dorsum 

 of 10 are black; caudal half of 7, all of 8 and 9, and sides of 10 

 blue ; there is some variation in the amount of blue on the prox- 

 imal segments ; anal appendages black, the superiors longer than 

 the inferiors and with a ventral basal tubercle (Fig. 10, No. 2), 

 the apices blunt and directed ventrad ; inferiors conical, sharply 

 pointed, and directed obliquely dorsad, about half as long as the 

 superiors. 



Female. — Color similar to the male. 



Head : with postocular spots sometimes separated from the 

 blue of the occiput. 



Thorax : mesostigmal plates black. 



Abdomen (Fig. 11, No. 20) : with terga 1-6 as in male, 7 with 

 a dorsal stripe reduced to a mesal line on the basal three-fourths 

 but suddenly widened at the apex ; eighth tergum black, with two 

 basal spots connecting with the pale lateral margins; dorsum of 

 9 and 10 black. 



Measurements : total length, male 27-32, female 30-34 mm. ; 

 length of abdomen, male 22-25, female 23-26 mm. ; length of hind 

 wings, male 16-18, female 18-20 mm.; width of hind wings, male 

 3-3.7, female 3.5-4 mm. 



Connecticut.— Branford, 21 July, 1920 (P. G.) ; Ellington, 8 July. 1026 

 (J. L. R.). 



Genus Argia Rambur 



Nymphs. — Caudo-lateral margins of the head not angulate; 

 labium without mental setae; abdomen without spinulose lateral 

 keels; gills half as broad as long, with cuticular pigment, the 



