NATURAL ENEMIES OF MOSQUITOES 161 



to swim, " yet they seemed liappy." As elsewhere stated, 

 they are viviparoiTS, and Dr. Yeazie says that a little 

 female will expel large numbers of the yonng at one time, 

 and that they can be raised in almost anything that holds 

 water. He has seen them swimming around under a layer 

 of ice, as unconcerned and active as they Avould have been 

 on a hot July or August day. 



I have been thus explicit in referring to these fish, and 

 have illustrated the best forms, for the reason that a very 

 practical use can be made of them. It was stated a num- 

 ber of years ago in Insect Life, that mosquitoes were at 

 one time very abundant on the Eiviera in South Europe, 

 and that one of the English residents found that they 

 bred abundantly in the water tanks, and introduced carp 

 into the tanks for the purpose of destroying the larvse. 

 It is said that this was done with success, but the well- 

 known food-habits of the carp seem to indicate that there 

 is something wrong with the story. If top-minnows or 

 sticklebacks had been introduced, however, the story 

 would have been perfectly credible, and it points to the 

 practical use of fish under many conditions. Some years 

 ago Mr. C. H. Eussell, of Bridgeport, Conn., described a 

 case in which a very high tide broke away a dike and 

 flooded the salt meadows of Stratford, a small town on 

 the north side of Long Island Sound. The receding tide 

 left two small lakes nearly side by side, and of the same 

 size. In one lake the tide left a dozen or more small fish, 

 while the other was Ashless. An examination by Mr. 

 Kussell in the summer of 1891, showed that while the 

 Ashless lake contained tens of thousands of mosquito 



