Entomology of the Illinois Elver. 167 



whitish, faintly lined or dotted; ocelli wanting. The 

 larva is unknown to me. 



iV^ maculalis Clem, {dispar Grote). 



These pretty moths were common about the small 

 lakes in northernlllinois August 4, being taken at Sand and 

 Fourth Lakes. They also occui-red at Cedar Lake June 

 19 and August 11, and at Fox Lake June 22; and were 

 taken in Urbana July 8 and 22 at electric lights. 



Paraponyx. 



The reasons for using this genus name are discussed 

 under Hydrocampa. The motlis are of a different faoies 

 from that genus, having narrower wings, and longstraight 

 dark lines on the posterior pair. The larvae differ from 

 all other known forms of the order in being provided 

 with filamentous tracheal gills. Their habits are hence 

 completely aquatic. 



It is stated that when the cocoon is formed the air 

 vessels of the leaf to which it is attached are tapped, 

 and the water in the cocoon is driven out and replaced 

 by air. 



P. ohscuralis Gr. [Fig. 1-7.] 



The favorite food of the larva of P. ohscuralis is the 

 leaf of Yallisneria spiralis, and it has also been found 

 upon Potamogeton nutans. The Vallisneria grows freely 

 at Station A, trailing in the slow currents at the mouth 

 of Quiver Creek, and here almost all our larvae were 

 found. They feed at first exposed on the leaf, but later 

 two or even three leaves are loosely webbed together 

 face to face by each larva, between which it remains con- 

 cealed while feeding. They are therefore hard to dis- 

 cover unless their hiding places are broken up by 

 seining or the like, when the larvaB may be seen swim- 

 ming about. In these retreats a fine but dense cocoon 

 may be found spun by the larva, in which the pupal 

 stage is passed. Full grown larvae and pupae were 

 obtained from these situations in July. In August, how- 



