510 MOSQUITOES OF NOETH AMERICA 



of Myrica. The grass forms a dense carpet with its thick root-stocks and dense 

 vascular roots, through which, here and there, appear small spaces of water with 

 pond-lily leaves. The whole layer is strong enough to support a man walking 

 on it, though it is very springy, and if one stands still, water appears upon the 

 surface and one sinks slowly. It was in the watery spaces among this grass carpet 

 that the egg-boats of Mansonia perturhans were found, and to the roots below 

 the larvffi are attached. It is essential for such a pond to remain in an undis- 

 turbed condition for it to make an ideal breeding place. Several other ponds 

 were seen with similar grass coating, but in most of them the layers had been 

 thickened by time and so densely grown up with sphagnum or even bushes of 

 considerable size that breeding of this mosquito was no longer possible. A very 

 large swamp has been formed by the damming of a stream to furnish power for 

 an electric-light plant. At the upper end of this swamp a large area, many acres, 

 of this grass occurs, forming an ideal breeding-place, but, owing to the changes 

 in the level in the water brought about by its use in the electric-light works, the 

 proper conditions seem to have been destroyed. In August the water was a foot 

 below its normal level, so that all the open spaces in the grass were dry and 

 covered by a hard crust. Oviposition at present is therefore impossible here. 

 However, it is not impossible that in a rainy season (the present season is a dry 

 one) this marsh might be permanently flooded and breeding conditions re- 

 established." 



North America, Canada to Florida, westward in the timbered country to 

 British Columbia. 



Sand Hill, Eideau, Canada, July 1, 1906 (J. Fletcher) ; Lincolnville, Maine, 

 August, 1908 (H. G. Dyar) ; Center Harbor, New Hampshire, August, 1903 

 (H. G. Dyar) ; Springfield, Massachusetts, June 7, 1903 (F. Knab) ; Westfield, 

 Massachusetts, July 14, 1903 (F. Knab) ; Rochester, New York, June 27 (W. 

 V. Ewers) ; Ithaca, New York, July 14, 1891 (J. H. Comstock) ; Lake Maxin- 

 kuckee, Indiana (B. W. Evermann) ; Delair, New Jersey, July 9, 1901 (W. P. 

 Seal) ; Siasconett, Massachusetts, October 31, 1900 (B. G. Wilder) ; Branford, 

 Connecticut, June 4, 1904 (H. L. Viereck) ; Lakeland, Maryland, August 8, 

 1895 (F. C. Pratt) ; Plummer's Island, Maryland, July 15, 1903 (W. V. 

 "Warner) ; Jackson's Island, Maryland, July 29 (H. S. Barber) ; Difficult Run, 

 Virginia, July 11, 1906 (Knab & Barber) ; Lake Drummond, Virginia, June 

 11, 1905 (H. S. Barber) ; Chesapeake Beach, Maryland, July 4, 1903 (A. 

 Busck) ; Myrtle, Georgia, May 19, 1906 (A. A. Girault) ; Sugar Loaf Beach, 

 Lake Okeechobee, Florida, March, 1906 (J. H. Egbert) ; Warner's Camp, north 

 shore of Lake Okeechobee, Florida, 1906 (J. H. Egbert) ; Melbourne, Florida, 

 April 4, 1901 (L. A. Peek) ; New Orleans, Louisiana, May 2, 1901 (H. A. 

 Veazie) ; Mississippi River Quarantine Station, Louisiana (E. Souchon) ; Tut- 

 wiler, Mississippi, August 2, 1904 (H. S. Barber) ; Little Rock, Arkansas, July 

 11, 1904 (H. S. Barber) ; Scott, Pulaski County, Arkansas, September 24, 1909 

 (J. K. Thibault, Jr.) ; St. Louis, Missouri, August, 1904 (A. Busck) ; Ames, 

 Iowa, June 27, 1906 (H. J. Quayle) ; Saxeville, Wisconsin, July 2, 1909 (B. K. 

 Miller) ; Big Fork, Montana, July 25, 1903 (Edith Ricker) ; Aweme, Manitoba, 

 June 30, 1906 (N. Criddle) ; Kaslo, British Columbia, July 2, 1903 (R. P. 

 Currie), 



Several records of Mansonia perturhans occurring in Cuba have crept into the 

 literature, but they are all erroneous and founded upon a misidentification. 

 Specimens of Psorophora jamaicensis from Cuba were at one time wrongly 

 identified as this species. Also the earlier records for the United States apply 



