970 MOSQUITOES OF NORTH AMERICA 



readily in artificial containers. In ground water it prefers the smaller collec- 

 tions, such as water seeping from springy hillsides and filling the smaller depres- 

 sions in soft ground, also ditches carrying but a trickle of water and similar 

 situations. It seems quite dependent upon the presence of algse." 



Tropical American mainland; Lesser Antilles. 



Cordoba, Mexico, January 6, 16, February 5, March 4, April 5, 1908 (F. 

 Knab) ; Eincon Antonio, Mexico, June 24, 1905 (F. Knab) ; Las Cascadas, 

 Canal Zone, Panama (A. Busck) ; Empire, Canal Zone, Panama (A. H. Jen- 

 nings) ; Ancon, Canal Zone, Panama, December 2, 1907 (A. H. Jennings) ; 

 Corozal, Canal Zone, Panama, November 30, 1907 (A. H. Jennings) ; East 

 La Boca, Canal Zone, Panama, December 6, 1907 (A. H. Jennings) ; Eio 

 Grande Eeservoir, Canal Zone, Panama, December 14, 1907 (A. H. Jennings) ; 

 Eoad to Comacho dam. Canal Zone, Panama, December 20, 1907 (A. H. Jen- 

 nings) ; Empire, Canal Zone, Panama, December 20, 1907 (A. H. Jennings) ; 

 San Pablo, Canal Zone, Panama, December 24, 1907 (A. H. Jennings) ; New 

 Amsterdam, British Guiana, May, 1907 (J. Aiken) ; Fort de France, Mar- 

 tinique, July 20, 1905 (A. Busck) ; Sao Paulo, Brazil (A. Lutz) . Eeported also 

 from Antigua, Dominica, St. Vincent, Grenada, Trinidad (Theobald) ; St. 

 Lucia (Theobald, Nicholls) ; Manaos and Teffe, State of Amazonas, States of 

 Para, Matto Grosso, Minas Geraes, Bahia, Alagoas and Eio de Janeiro, Brazil 

 (Peryassu) ; Argentina (Theobald, Autran). 



Theobald records this species from Jamaica, on the strength of specimens 

 taken by Dr. Grabham in 1899 and " not met with since." We suspect that 

 there is something wrong with this record. The species inhabits the South 

 American faunal region of which the I^esser Antilles are part, but does not, 

 in our experience extend its range into the Greater Antilles, which comprise an 

 essentially different faunal region. We should not, therefore, expect to find 

 it in Jamaica, and accordingly omit the locality pending confirmation. The 

 later records, by Theobald, of this species from Cuba, Haiti and Porto Eico are 

 open to the same objection. In fairly abundant material from these islands 

 we have never encountered a specimen of A7iop]ieles argyritarsis. We suspect 

 that the records are merely due to the confusion of this species with A. albi- 

 manus and that they are in reality referable to the latter species. It should be 

 further noted that specimens of A. alhimanus with the hind tarsals broken may 

 be easily mistaken for argyritarsis. Such specimens may be recognized by the 

 pale ocher-yellow color of the light scales on the wings, these scales usually being 

 pure white in argyritarsis. 



Much confusion has arisen in the literature owing to the fact that Anopheles 

 albimanus has been treated as a variety of A. argyritarsis, under the name 

 variety alhipes Theobald. The two are distinct in all their stages and often 

 occur quite independently. 



Anopheles argyritarsis has been reported by Howard from New Orleans, 

 Louisiana, but we believe that this record is either based upon an accidentally 

 introduced specimen or more likely upon a misidentification. The records from 

 the Argentine are open to question and are probably based upon misidentifica- 

 tions of the closely similar Anopheles albitarsis Lynch Arribalzaga. 



Our specimens show considerable variation in the development of the scale- 

 tufts at the apical angles of the abdominal segments and a tendency toward the 

 formation of local races appears to be indicated. A specimen from British 

 Guiana shows very well developed tufts of strongly outstanding, broadly ovate 

 scales, well differentiated from the scales of the dorsum. A series of specimens 

 from Panama shows incomplete tufts, the scales less differentiated from the 

 dorsal ones and gradually becoming more erect toward the apical angles of the 

 segments. A specimen sent by Doctor Lutz from Sao Paulo, Brazil, agrees with 

 this form in the abdominal tufting. Finally, a series reared by Knab in south- 

 ern Mexico shows no trace of tuftings. All these specimens agree very closely in 



