CORDULEGASTER. 13 



15. Cordulegaster Sayi. 



Sklys, Synopsis ties Gomphines, p. 85, No. 106; second additions, p. 40. Monoftr. des Gomph. 

 p. 331, No. 109.— C. lateralis Scudd., Proc. Boston S. N. H., X. p. 211. 



Plate III., fig. 2. 



Locality : Maryland ; Cambridge and Chicopee, Mass. July 1-4, 

 1860. R. H. Wheatland. Length, 40 ram. 



Head short, broad. Breadth twice the length, sides straight, rounded 

 off behind so that the hind-border in front of prothorax is half the 

 width of fore-border. Vertex flat. Hind-l)order somewhat indented. 

 Eyes small, round, prominent, placed at forward lateral angles of fore 

 border of head, with triangular piece projecting inward. Ocelli visible, 

 especially the lateral ones. Antennae 7-jointed, tapering, slender ; the 

 2 basal joints thicker and more rounded, 3d longer than 2d ; joints 3 

 to 7 form a rather slender seta. Mask large, extending a little beyond 

 the middle legs, triangular, contracted behind ; the sides bent up, hol- 

 lowed back of fore-border, which is prolonged into a bifid tip, sur- 

 mounted by a short hairy comb. Palpus broad, enlarged at inner bor- 

 der, and deeply denticulated, the denticulations of the opposite palpi 

 closely fitting into one another ; movable hook short, sharp, and slender. 

 Prothorax half the length of head, and two thirds the breadth, indented 

 in the middle, raised at fore part in small transverse lobe, at hind part 

 border raised, and thicker in the middle. Stigmata large, open. Legs 

 very hairy, flattened, formed for running. Femora angular, thick, and 

 a little bent; tibiae about equal in length to femora. Tarsi 3-jointed, 

 more than half as long as tibiae. 1st joint short, 3d longest ; claws very 

 sharp. Hind legs reaching the 7th segment. Abdomen long, i-ounded 

 above, tapering gradually. Largest part at middle, as wide as head ; 

 no dorsal hooks. Segments 8 and 9 with lateral spines. Segments of 

 about equal length. 3 anal appendices of twice length of 10th seg- 

 ment, pyi-amidal, sharp ; superior somewhat shorter ; lateral ones very 

 short and sharp. At the end of 8th ventral segment a bifid triangular 

 vulva nearly equal in length to 9th segment. 



• Have seen one not full-grown female nympha, length 30 mil., from 

 Maryland, which is figured. Coll. Hag., and two fuU grown from Chico- 

 pee, Mass., length 40 mm. Coll. Mus. Comp. Zool. 



It was thought best to refer this nympha to C. Sai/i, as this is the 

 only North American species very similar to C. anmilatus. 



