REPORT ON MOSQUITOES. 99 



winter they may be carried for lioiirs without water, until the 

 mouth is completely closed with a plug of ice and they are appar- 

 ently dead; yet upon thawing out they will be as lively as ever. 

 But, notwithstanding this apparent hardihood they in common 

 with the others of this genus are difficult to hold in captivity in 

 large numbers, as most anglers can testify. The common name 

 of this species about Philadelphia is 'bullhead' or 'Bullhead min- 

 now.' No doubt because of the very blunt head and snout. 



"It is probably the most valuable species of Fundulus for the 

 purpose of mosquito prevention, being a top feeder and a great 

 forager. And if any one of the Fundtthts will remain and multi- 

 ply in land-locked waters it will be this species." 



My personal experience is that in a one-quart fruit jar I have 

 kept half-grown specimens for months, and in a cistern many 

 years ago always had a supply of from ten to a dozen. While, 

 some died, of course, most of them lived a long time and even 

 wintered, but never multiplied. There is no doubt that in water 

 barrels and cisterns this species would flourish for the season at 

 least. 



The females are nearly uniformly olivaceous, lighter below. 

 The males are dark greenish, with many narrow, irregular, sil- 

 very bars on the sides and the belly yellowish or orange. The 

 sides are also more or less spotted with white or yellow. 



FUNDUI^US DIAPHANUS. 



Presh-zuater Killy. 



The length of this species is given as about four inches, but five 

 inches will be nearer the mark. Its range is given as Coast of 

 Maine to Cape Hatteras, ascending streams to their fountain 

 Tiead; hence abundant in lakes throughout New York. It is the 

 most graceful and active species of the genus Fundulus found in 

 New Jersey waters. While having about the same range as 

 heteroclitus its movements are confined more generally to the 

 channels and currents, evidently preferring clear open water. 

 The young mingle and move with those of heteroclitus, but as 

 they grow larger they separate more and more. It may be set 

 down as a rule that in places where heteroclitus are abundant, 

 ■diaphaiius will be scarce, and vice versa; indicating that they dif- 

 fer radically in their choice of conditions." 



Dr. Bean in his "Fishes of New York," states that this species 

 thrives better in aquariums than any other killy save heterocli- 



