MOSQUITO MIGRATIONS 339 



" Doctor Smith points out that there are many hundreds of acres along the 

 shores of Barnegat Bay, and especially along its upper portion, where a very 

 small amount of diking will serve to keep out salt water and fit the land for 

 certain truck crops. He also shows that along a large portion of the Barnegat 

 Bay line cranberry plants grow annually to the very edge of the salt-marsh line, 

 but that these could not be improved because there was no way out across the 

 marsh for surface water. With the ditching going on, this land will become 

 available in large part at least and will allow the owners to derive a revenue 

 from land which is at present practically nonproductive. Of course taxes will 

 then be raised and the income of the townships in which this land lies will be 

 increased.'^ 



INFLUENCE OF WIND ON THE DISPERSAL OF MOSQUITOES. 



The majority of mosquitoes do not appear to fly very far. Those of the genus 

 Anopheles are seldom found more than a half mile from their breeding-places. 

 The evidence as to mosquitoes being carried by winds is unsatisfactory and more 

 or less conflicting ; this is doubtless due partly to the fact that species of differ- 

 ent habits are involved and partly to the unscientific character of the observa- 

 tions. It must also be remembered that the records are sure to be shaped in 

 accordance with the preconceived ideas of the observer. The common house mos- 

 quitoes are seldom found far away from their breeding-places. The salt-marsh 

 mosquitoes, however, migrate, possibly sometimes aided by the wind, but, as 

 recent evidence shows, more probably flying into the wind. The more careful 

 observations on mosquito behavior show that for the most part mosquitoes will 

 not fly when there is a strong breeze. Possibly the only exceptions are the mos- 

 quitoes of the northern prairies, where the low night temperatures oblige them 

 to be active during the day in spite of the constant high wind. Full accounts of 

 two remarkable mosquito migrations, observed by the Hon. J. D. Mitchell, of 

 Victoria, Texas, are given on pages 33 to 34 of "Mosquitoes" (Howard). 

 These are of sufficient interest to quote in full : 



" I have witnessed, in my life, two migrations of mosquitoes, that will always 

 be fresh and vivid in my memory. 



" Where the Colorado Eiver empties into Matagorda Bay, a marsh is formed 

 over the lowlands, by a raft in the river; this marsh contains about eighteen 

 square miles, and is a magnificent breeding-place for mosquitoes. 



" 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 Creek on the 

 west, and the Calhoun County north line on the north (refer to coast maps 

 of Texas). The distance between my ranch property and the marsh above 

 described is, by bay route, about forty miles ; the way the crow flies, about thirty- 

 five miles. My ranch was situated on Carancahua Bay, near the north end of 

 land. 



" The first migration occurred in October, 1879. There had been an overflow 

 from the upper country, which filled the aforesaid marsh, but the balance of that 

 section was very dry and needing rain, and there were no mosquitoes. A fairly 

 strong easterly wind had been blowing for three days ; on the evening of the third 

 day the mosquitoes arrived, flying high, about flfty feet, and looking like a cloud 

 or mist over Carancahua Bay. At the ranch they set everything on fire that had 

 blood in it, and all work was suspended by unanimous consent. Cattle and 

 horses rounded-up milled continuously ; all work stock was turned loose as quick 

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