218 MOSQIHTOES OF NORTH AMERICA 



in others, particularly the group Microculex, the palpi are straight, blunt at 

 apex, and more or less shortened. 



The genus Culex, as conceived by Linnaeus, comprised a very extended group, 

 including besides the CuMcidse as now understood, Simuliidae, Chironomidae, and 

 even a dung-inhabiting fly. The first species, Gidex pipiens, has been uniformly 

 considered to be the type, perhaps because it is the " most common or officinal " 

 species included. By his Gulex pipiens Linnseus evidently had in mind any 

 mosquito with short palpi in the female, including the genera Culex, Culiseta, 

 and Aedes as we now know them. To properly apply the name Culex, therefore, 

 it is necessary to restrict the species pipiens of Linnaeus. N"ow, Linnaeus pro- 

 posed Culex vulgaris in 1736 (Act. Ups., 31) and Culex alpinus in 1737 (Mora 

 Lapp., 364), but as these names are before the tenth edition of the Systema 

 Naturae, they are arbitrarily ruled out by the nomenclatorial codes. Their first 

 mention after 1758 is in the second edition of the Tauna Suecica (p. 464, 1761) 

 as synonyms of Culex pipiens. Later, however, (Mora Lapponica, 2 ed., 380, 

 381, 1792), he revives the names and discusses the two species at some length. 

 We infer that his Culex vulgaris represents principally a species of Simuliwm, 

 perhaps partly confused with Culex {Aedes) and that the Culex alpinus repre- 

 sents an Aedes, perhaps the same as Aedes nigripes Zetterstedt. This consti- 

 tuted an elimination from the general Culex pipiens conception of Linnaeus of 

 the Aedes element, leaving Cvlex (in the present sense) and Culiseta. The re- 

 striction to the common house mosquito seems to have been generally made on 

 account of Linn^us's own references to Eeaumur and others, who seem to have 

 had under observation Culex pipiens as here understood. The Culiseta appear 

 to be rarer and less domestic and are excluded from consideration as being less 

 " common or officinal." In 1776, De Geer described Culex communis (Mem. 

 Hist. Ins. 316, pi. 17, S. 14-15), which Pabricius referred to the s3raonyniy of 

 CuJex pipiens (Species Ins., ii, 469, 1781). The larvae figured by De Geer 

 show his species to have been an Aedes, and this acts as a restriction on the 

 Culex pipiens of Linnaeus and confirms the opinion above arrived at Theobald 

 therefore appears to be justified in recognizing as the true pipiens, the common 

 house-mosquito of Europe breeding in artificial receptacles. It is altogether 

 possible that there are several species so breeding in Europe — ^in America we 

 have five along the Atlantic seaboard — but if so they never have been differen- 

 tiated. We therefore consider as pipiens the common rain-barrel inhabiting 

 species of Europe and identify with it that one of our common rain-barrel species 

 which agrees in the male genitalia with the one from Europe. 



The genus Culex, as treated here, rests essentially on the characters of the 

 larvae and the male genitalia ; it includes forms which differ considerably from 

 the common adult type. Most striking of these more specialized forms are those 

 with the reduced male palpi, for which a number of genera have been proposed 

 (Micraedes, Aedinus, Isostomyia, Tinolestes) ; but there are no supporting 

 characters in the female, larva, or male genitalia that would warrant their 

 separation from Culex. In fact, the forms with short male palpi intergrade 

 with the typical forms with long palpi through such species as Culex ocellatus, 

 where the male palpi are only slightiy shortened ; this intergradation doubtlessly 

 wiU be made more complete by the discovery of other tropical forms, for our 

 knowledge of the neotropical species of Culex is as yet very fragmentary. 

 Another specialization, the lengthening of the antennal joints, occurs in Culex 

 (Tinolestes) latisquama, but here again intermediate forms lead up from the 

 general type. The modifications of tiie scale vestiture, and the genera founded 

 on them, need not be discussed here. It should be pointed out, however, that 

 two other genera, which we have treated as distinct, might, perhaps, with more 

 propriety be treated as subgenera of Culex. These are Imtzia and Carrollia. 

 The close relationship of these genera with Culex is obvious, and, in Lutzia, the 



