OF WASHINGTON, VOI.UMK XI, 1909 37 



vestiture of the mesonotum is distinctly different in this group 

 from that of the foregoing f>if>icns group, and serves readily to 

 distinguish them, without the criterion of the male genitalia. 



Culc.r salinarins is a close ally of siniilis Theobald, and may 

 be considered to take its place in North America. Culex siniilis 

 inhabits the Antilles, while salinarins is found throughout the 

 eastern part of North America, from Maine to Florida and 

 westward to the Mississippi \ alley. The two species are doubt- 

 less derived from a common American stock, but have been long 

 separated, and have developed well-marked specific characters. 

 Cnlc.v factor represents these species along the Pacific coast of 

 .Mexico and Central America. 



Culex factor Dyar and Knab. 



In this species, which we have not figured, the genitalia are 

 ot the type seen in salinarius and siniilis. The outer plate of 

 the harpagones has above a large tooth, followed by three 

 slender, well-separated ones below, the lower angle forming a 

 large rounded angle, too large and broad to be described as a 

 tooth; a long horn-like tooth arises in a different plane, and 

 exceeds the other teeth in length. The lower plate of the harpa- 

 gones is of the usual form. The harpes have the erect portion 

 crowned with' spines as usual, the basal projection very long and 

 curved, as in our figure of salinarius (fig. 7, b}. 



The species is especially characterized by the fewness of the 

 central teeth of the outer plate of the harpagones, and the long 

 horn-like tooth, which exceeds the other teeth in length. The 

 scales of the mesonotum are hair-like and sparse, but they are 

 larger and coarser than those of salinarius and siniilis. 



The species inhabits the west coast of Mexico and Central 

 America, seeming especially at home in salt water. Most of our 

 specimens were bred at Salina Cruz, Mexico, from salt pools 

 behind the beach, and Mr. Jennings has obtained the species in 

 the La Hoca swamp in the Canal Zone, Panama, which is a low 

 swamp on the Pacific side of the Isthmus. We have also speci- 

 mens from Tehuantepec and Santa Lucrecia, Mexico, bred 

 from fresh water, showing that the species is not confined to 

 salt water. It is evidently much like our salinarius, which is 

 most abundant near salt marshes, although generally distributed 

 throughout the country, but perhaps this is more addicted to 

 actually salt water than salinarius is. 



Culex similis Theobald. 



The genitalia (Plate in, fig. 8) have the harpagones and 



harpes essentially as in salinarius, but are especially distin- 



