98 Parasitic Arthropoda 



Aside from their importance as carriers of disease, mosquitoes are 

 notorious as pests of man, and the earHer literature on the group is 

 largely devoted to references to their enormous numbers and their 

 blood-thirstiness in certain regions. They are to be found in all 

 parts of the world, from the equator to the Arctic and Antarctic 

 regions. Linnaeus, in the "Flora Lapponica," according to Howard, 

 Dyar and Knab, "dwells at some length upon the great abundance of 

 mosquitoes in Lapland and the torments the-y inflicted upon man and 

 beast. He states that he believes that nowhere else on earth are they 

 found in such abundance and he compares their numbers to the dust 

 of the earth. Even in the open, you cannot draw your breath without 

 having your mouth and nostrils filled with them; and ointments of 

 tar and cream or of fish grease are scarcely sufficient to protect even 

 the case-hardened cuticle of the Laplander from their bite. Even in 

 their cabins, the natives cannot take a mouthful of food or lie down 

 to sleep unless they are fumigated almost to suffocation." In some 

 parts of the Northwestern and Southwestern United States it is 

 necessary to protect horses working in the fields by the use of sheets or 

 burlaps, against the ferocious attacks of these insects. It is a sur- 

 prising fact that even in the dry deserts of the western United States 

 they sometimes occur in enormous numbers. 



Until comparatively recent years, but few species of mosquitoes 

 were known and most of the statements regarding their life-history 

 were based upon the classic work of Reaumur (1738) on the biology 

 of the rain barrel mosquito, Culex pipiens. In 1896, Dr. Howard 

 refers to twenty-one species in the United States, now over fifty are 

 known; Giles, in 1900, gives a total of two hundred and forty-two 

 for the world fauna, now over seven hundred species are known. 

 We have found eighteen species at Ithaca, N. Y. 



All of the known species of mosquitoes are aquatic in the larval 

 stage, but in their life-histories and habits such great differences occur 

 that we now know that it is not possible to select any one species as 

 typical of the group. For our present purpose we shall first discuss 

 the general characteristics and structure of mosquitoes, and shall 

 then give the life-history of a common species, following this by a 

 brief consideration of some of the more striking departures from what 

 have been supposed to be the typical condition. 



The Culicidae are slender, nematocerous Diptera with narrow wings, 

 antennffi plumose in the males, and usually with the proboscis much 

 longer than the head, slender, firm and adapted for piercing in the 



