240 SECOND REPORT OF THE STATE ENTOMOLOGIST. 



4. Nerioura NIVALIS. The Large '^ Snow-Jly." The '■' Shad-fly. '''' 



Black ; wings griseous, faintly banded, double the length of the abdo- 

 men. 



Length, males somewhat under, females over half an inch ; wings ex- 

 pand about an inch. 



Head cov€,xed with minute whitish hairs, which are longer and more ob- 

 vious beneath the bases of the antennae and around the mouth. Vertex 

 with an obtusely impressed transverse line immediately back of the two 

 posterior stemmata, and a longitudinal medial one, reaching from the for- 

 mer to the neck. Antennae black, clothed with very short minute hairs, 

 slender, setaceous, as long as to the tips of the wings in the males and 

 somewhat Shorter in the females, composed of about sixty joints; basal 

 joint short-cylindrical, its diameter double that of the third and following 

 joints; second joint intermediate between the first and third in diameter, 

 its length and breadth about equal ; the remaining joints obconic, grad- 

 ually diminishing in diameter and increasing in length toward the tips. 

 Palpi clothed with very short, minute hairs, black; basal joints of the 

 maxillaries lurid and slightly diaphanous, penultimate joint rather the 

 shortest and obconic, the joint preceding it longest and obconic, the ter- 

 minal joint oval, and scarcely as thick as the others. Prothorax square, 

 in the females scarcely broader than it is long, somewhat narrower ante- 

 riorly, posterior angles rounded, all the margins slightly and obtusely ele- 

 vated, the posterior one more obviously so, often with a dull fulvous spot 

 at the base, or with this color spread over the posterior part of the raised 

 margin, and more rarel}^ a similar spot at the middle of the apex ; disk 

 sometimes showing an impressed transverse line, and a longitudinal dor- 

 sal stria. Exposed portion of the mesothorax much elevated above the 

 plane of the prothorax, forming a transverse ridge between the bases of 

 the wings ; clothed with short hairs ; often with traces of dull fulvous 

 around the wing-sockets; the portion of the mesothorax and metathorax 

 covered by the wings smooth and shining. Abdoinen reaching but half 

 the length of the wings; sutures of the tergum in the female more or less 

 widely marked with dull rufous; tip, in the female only, furnished with 

 two short, filiform setae, scarcely equalling in length the segment to which 

 they are attached ; setae pale lurid, sub-diaphanous, hairy, composed of 

 about eight joints. Each segment of the venter with two transverse im- 

 pressions, one situated toward each posterior angle. Male organ ex- 

 serted, forming a conical lurid point near the base of the last ventral seg- 

 ment. Femurs cylindrical, black, clothed with white hairs, which are 

 longer and more distinct in the females, inner side with a narrow deep 

 groove which is dilated toward the apex. Tibice cylindrical, about half 

 the diameter of the femurs, grooved, lurid-brown, diaphanous, the ends 

 and inner sides black; apex slightly incurved and armed with two short 

 spines on the inside. Tarsi black, composed of three joints, whereof the 

 middle one is slightly shorter; two claws and an intervening pellet at the 

 tips. Wings griseous, when closed showing faintly two paler bands, one 



