EXPEUHEEXT STATIOX EEPOET. 665 



iiuu'li larger and lias nover lu'cn taken earlier than the first days of 

 May, and more usually much later. It dc'cs not occur in woodland 

 pools, except rarely in such as may be close to the open fields, but 

 is usually found in ()])en swamp areas, lot-pools with clayey bot- 

 toms, etc., wlicre tlic lar\-a' are found sometimes in immense num- 

 bers, crowded tnoethei- and associated with no other species. This 

 latter form is connnon until the end of the season. It seems proba- 

 ble that we liave here a dimorphic species to deal with, the scant 

 early brood l)eing parent to the succeeding generations. Certain 

 it is that the large form has been found in May in pools that were 

 not in existence the year previous, indicating conclusively that the 

 eggs had been laid tlie same year. 



CiiJcx sif/iiifcr. it has been intimated, hihernates in the larval 

 condition. This we wcvv at first inclined to doubt, since all of our 

 ])re\'ious collections of lar\';r of this species had heen made in Sep- 

 temher and all came 1o malurity before the end of that month. To 

 test the point more thoroughly, however, Mr. II. O. Marsh, of 

 Chester, collectcMl all the larval contents of a treediole April 22d, 

 in which sujnifrr larvjv were found the jireceding year. Larvse of 

 ('idc.v f)'iseriatus. one-third grown, were found in some numbers, 

 but no sifiuifcr larva' were among them. In Se])tember Mr. Dick- 

 erson found in the same tree-hole small and half-grown larvne of 

 s'tgnifer, and u]) to the time of writing { Xovember 10th) many of 

 these are still in the laboratory and none have reached the pupal 

 stage. In confinement in glass jars, however, even though kept in 

 water taken from the treediole, larvrc do not obtain the proper 

 nourishment necessary to their develo]unent, and unless they are 

 almost full gro\\ii, will merely continue to exist, scarcely growing 

 larger, and may linger on for months, as has been demonstra,ted 

 with various other species. In vie\\- of this fact Mr. Marsh was 

 again requested to examine the "siynife)' hole," and on November 

 iTtli he secured a full brood of the larv:e in all stages, from small 

 to almost full grown. With them were two large larviie of Cidex 

 trisci'icH IIS. ^Ir. Marsh said that there was about nine inches of 

 water in the hole, and that the surface was covered by three-fourths. 

 of an inch thickness of ice; novertlu'less, he said the larvae were 

 moving ahout actively. It a]ipears, therefore, that this species does 

 hibernate as a larva, and that the adults emerge early in the spring 

 of the followin,g vear. It seems not to breed continuously through- 



