AQUATIC INSECTS IN NEW YORK STATE 



443 



the Corydalinae. The more important of the distinctive char- 

 .xicters of the subfamilies are included in the following tables. 



TABLE TO SUBPAMIL-IES 



Adults 

 a \ccessory veins of radial sector on the front side of 



vein R3 [fig- 23] ; ocelli wanting; fourth segment of ^ . ^ ^ . ^ . ^ ^ ^ 



tarsi prominently bilobed 



■aa Accessory veins of radial sector on the posterior side 

 of vein R. [fig- 24, 25, 26] ; ocelli three; fourth seg- 

 ment of tIn-si obscurely or not at all lobed Corydalinae 



Larvae 

 a Anal prolegs wanting; lateral filaments only seven ^ . ^ . ^ ^ ^ 



pairs, and distinctly jointed. 



■aa inal prolegs one pair, provided with claws; lateral , • „ , ^ 



fitments eight pairs, slightly or not at all jointed .Corydalinae 



Egg masses 

 1 rr.1 p^n . S ial idi n a e 



a Eggs always in one layer [pl.51] Corydalinae 



<ia Eggs in more than one layer [p1.d2] *- " ^ ^ 



Eggs 

 a Distal portion of micropylar projection cylindric, 



twice as long as broad, joined to the egg by a short ^ ^ ^ ^ 



neck [fig.20] :"\'\" 



aa Distal portion of micropylar projection nearly globu- , , . „ ^ 



^^- jomed to the egg by a long neck [fig.20] Corydalinae 



Subfamily sialidinab 

 The adult members of this subfamily are all much smaller 

 than those of the Corydalinae; the ocelli are wanting; the acces- 

 sory Teins of the radial sector in both pairs of wings arise 

 from K and extend forward, giving the insect a very charac- 

 teristic mode of flight; the fourth segment of the tarsi is promi- 



iiently two lobed. 



The subfamily includes a single genus Sialis. 



siALis Latreille • 



Besides the characters of the subfamily given above, the fol- 

 lowing additional generic characters should be added: 



Adult Body and wings black or ferruginous; prothorax 

 ouadran-ular, almost equal in width to the head, not so long as 

 the mesothorix and metathorax combined; ocelli wantmg; an- 



