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



Genus Macromia Rambur 



Nymphs. — With prominent frontal horns; teeth on proximal 

 segments of the labial palpi with deep incisions between them; 

 spines of the ninth abdominal segments not reaching to the apices 

 of the terminal segments. 



Adults. — ^X^/'ith sectors of the arculus united for some distance 

 beyond the latter; triangle free or with one cross-vein; subtri- 

 angle present, the cubito-anal cross-veins usually three in number ; 

 area between M4 and Cu^ in front wings not widened apically ; no 

 dark spots on wings ; eyes meeting in a line of considerable length ; 

 abdomen of female without a long forked process on sternum of 

 segment 8 ; abdomen of female and male slightly compressed. 



For literature dealing with Macromia adults, see 

 Williamson, E. B. Proceedings U. S. National Museum, 37: 369-398: 

 1907, pis. 35-36. 



Key to Species 

 Males and Females 



Dorsum of thorax without yellow marks ; average length of 

 abdomen 49 mm. (47-52 mm.) illinoiensis 



Dorsum of thorax with distinct yellow marks ; average length of 

 abdomen 59 mm. (56-61 mm.) taeniolata 



Macromia taeniolata Rambur 



Histoire naturelle des insectes. Neuropteres, 139: 1842. 



Adult, male. — Color black and yellow. 



Head: with pale transverse band just above the clypeus ; occi- 

 put black. 



Thorax: with faint stripes on the mesepisternum in front and 

 the usual lateral stripe on the metepisternum ; sides of the thorax 

 showing metallic green. 



Abdomen: black with transverse interrupted band on segment 

 2 ; triangles on 3 to 7 inclusive and basal spots on segment 8 pale ; 

 triangles on 7 united, forming a transverse band ; anal appendages 

 in dorsal view show the superiors with a slight tubercle near 

 middle; tips pointed in lateral profile, bases yellow. 



Measurements : total length, male 75 to 84, female 81 mm. ; 

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

 46-52, female 51 mm.; width of hind wings, male 12, female 

 14 mm. ; length of stigma, male and female, about 4 mm. 



Specimens examined in the Museum of Comparative Zoology. 



Macromia illinoiensis Walsh 

 Journal of the Academy of Natural Sciences of Philadelphia, 397, 1862. 

 Nymph. — Color of alcoholic specimens uniform brown or 

 nearly black. 



Head: palpi with 6-7 lateral spines and a slender end hook; 



