22 MOSQUITOI'JS 



huiulred yards of tlio surf. As it is al)Soluti'ly isolated 

 from trees, and as the mosquitoes do not appear during: 

 a lull in the breeze, but only after several days of land 

 breeze, it appears to him that the popular view of the 

 intluence of land breezes upon spreadini;- mos(piitoes sea- 

 ward is not wholly without foundation. 



All the evidence so far adduced refers to nior(> or less 

 normal conditions and, in fact, such conditions are the 

 only ones which need i)racticalh' bo considered. Under 

 very exceptional conditions, however, it seems i)erfectly 

 plain that mos(piitoes may mi.^rate for considerable dis- 

 tances ; two such instances are described in the following 

 lines quoted from a recent letter received from the Hon- 

 orable J. D. Mitchell, of Victoria, Tex., a reliable ob- 

 server and a naturalist. 



. . . I have witnessed, in my life, two mip:rations of mos- 

 quitoes, that will always I)e fresh and vivid in my memory. 



Where the Colorado River emjities into Matagorda Bay, a 

 marsh is formed over the lowlands, ))y a raft in the river ; this 

 marsh contains about eighteen square miles, and is a magnifi- 

 cent breeding-place for iiiosciuitocs. 



I used to ranch it on the peninsula-like body of land, formed 

 by Carancahua Bay on the east, Matagorda Bay on the south, 

 Keller's Bay and ('reck on the west, and the Calhoun ( 'onnty 

 north line on the north (ref«'r to <*oast maps of Texas). Tiic dis- 

 tance between my ranch property and the niarsli al)(>ve described 

 is, by bay route, about forty miles ; the way the crow Jlies, about 

 thirty-five miles. My ranch was situated on Carancahua Bay, 

 near the north end of land. 



The first migration occurred in ()ctol)er, 1S7!». There had been 

 an overfU>\v from the upper country, which lilled the aforesaid 



