254 AGRICULTURAL EXPERIMENT STATION. 



force. In the Black River Swamp they were found in the same 

 condition at about the same time and so, on June 30th, mostly 

 pup?e were found in woodland pools on the borders of Spring 

 Lake, near Trenton. July 21st, there was a young brood in the 

 pools surrounding Lake Hopatcong, and a few days later mature 

 larvae and pupae were taken everywhere in pools in the Hacken- 

 sack Valley. The entire Passaic and Hackensack Valleys were 

 kept under observation during 1903, as were also those large 

 swamp areas in Essex and Morris Counties and always syivestris 

 was the dominant species. Captures of adults sent in from this 

 territory always showed syivestris present, and that species breed- 

 ing in a swamp area at Vailsburgh, become common in the send- 

 ings of adults from Montclair and South Orange. 



From the region of the Delaware the open marsh areas almost 

 always turned out syivestris in numbers. Mr. Grossbeck found 

 it the dominant species between Trenton and Bordentown. Mr. 

 Seal sent it in by the hundred from the swamp areas near Delair 

 and toward the river. Mr. Viereck found the species along the 

 Big Timber Creek region and in the marsh areas south of Cam- 

 den. He also found it in the Cape May inland swamp region. 

 This is, therefore, essentially a swamp species, but it does not oc- 

 cur in deep or dark swamps. Mr. Brakeley never found it in the 

 huckleberry swamps of Lahaway and indeed rarely sent in the 

 species in an}^ stage, nor did I find it in my cranberry swamp col- 

 lections. 



By far the greater number of larvae were taken in permanent 

 water areas, but many of the woodland pools in which it occurred 

 w^ere temporary in the sense that they usually dried out before the 

 summer was over. It was never sent in from gutters or lot rain 

 pools or from foul waters at any time. Mr. Viereck found it once 

 in a barrel at Cold Spring, Cape May County. In New Bruns- 

 wick a brood was found in a lot pool August 12th, larvae being- 

 mature and pupae already present ; a second brood w^as found Sep- 

 tember 23d in a similar stage and there may have been a brood 

 in the interval. This is a low springy place, which rarely dries 

 out entirely and which fills readily with even a light rain. The 

 latest collections of larvae were made during the early days of 

 October, adults emerging about the middle of the month. 



As for the habits of the larvae they offer nothing that is pecu- 

 liar. They are dependent upon atmospheric air and hence are 

 readily destroyed by any of the oil coverings. The pupal stage 

 varies in length according to temperature, but is usually short — 

 two or three days during the summer. 



