No. 39] ODONATA OF CONNECTICUT: GOMPHIDAE 153 



short ; hardly surpassin_^ the base of the tenth segment, straight 

 but not closely oppressed ; tenth segment half as long- as the ninth 

 and a little shorter than the appendages ; dorsal hooks represented 

 by low inconspicuous rudiments on segments 3-9, with traces of 

 the median impressed line on the anterior end of the middle 

 segments. 



Measurements : total length, 32 mm. ; length of abdomen, 20 

 mm., width 7 mm. ; length of hind femora, 5.6 mm. 



Description from Needham 1901, p. 454. 



Adult, male. — Color brown marked with greenish yellow. 



Head : greenish yellow except ocellar area and a transverse line 

 on the front; rear of head pale on sides, remainder brown. 



Thorax: meso- and metathorax as in Fig. 22, No. i, the mes- 

 episterna each with a variable yellow stripe and streak above the 

 mesopleural suture; interpleural and metapleural sutures lined 

 with black. 



Abdomen : brown, terga 2-7 with a pale mesal line, 8 with a 

 mesal spot at base; about half the lateral surfaces of terga 1-3 

 and 9 pale ; obscure lateral marks on 4-8 ; superior anal appen- 

 dages in dorsal view show teeth on lateral and mesal surfaces, that 

 on the mesal surface sharply outlined. 



Female. — Vulvar lamina consisting of subtriangular plates a 

 little less than one-third the length of segment 9 (Fig. 20, No. 

 13) ; occipital ridge depressed at center (Fig. 21, No. 19) as in 

 borealis; in general with more pale color than the male. 



Measurements : total length, male 49, female 50 mm. ; length 

 of abdomen, male 34, female 35 mm. ; length of hind wings, male 

 20, female 32 mm. ; width of hind wings, male 8, female 8.5 mm. 



Described from material in collection of P. P. Calvert. 



Gomphus exilis Selys 



Bulletin de rAcademie royale . . . de Belgique, 21 : .SS : 1854. 



Nymph (PI. iii, Fig. 7). — Color dark brown. 



Head : labium with median lobe as broad as long, contracted 

 behind the middle, the lateral margins nearly parallel ; palpi with 

 about 6 teeth on the mesal margin ; antennae with the third seg- 

 ment longer than all the rest together; cylindrical, not flattened. 



Thorax : wing-pads extending to the fourth abdominal segment. 



Abdomen : lateral spines on segments 6 to 9 inclusive, the ninth 

 segment twice as long as the tenth, the spine of the ninth half, or 

 less than half as long as the tenth segment; width of the ninth 

 abdominal segment at caudal margin, measured inside the spines, 

 less than the length on the dorso-meson ; dorsum with distinct 

 sharpened dorsal hooks on segments 6 to 9 and prominences on 

 3 to 6. 



Measurements : total length, full grown, 23 mm. ; length of 

 median lobe, 3.5 mm. wide by 2.5 mm. long; length of hind 

 femora, 4.5 to 5 mm. 



