70 PREVENTIVE AND REMEDIAL WORK AGAINST MOSQUITOES. 



female is dull in color, without conspicuous markings, while the male 

 is marked with irregular red splotches on the sides and has a circular 

 dark spot on each side. The fish is a rapid breeder and thrives and 

 multiplies in captivity in water-tanks, reservoirs, and fountains, and 

 garden- tubs in which aquatic plants are kept. They are greatly 

 used in this way both in the towns and on the estates to reduce the 

 annoyance of mosquitoes. Tn 1905 this fish was introduced by the 

 Imperial Department of Agriculture of the British West Indies from 

 Barbados into St. Kitts, Nevis, and Antigua. In 1906 it was intro- 

 duced into Jamaica and in 1 908 into St. Vincent and St. Lucia, and into 

 Guayaquil in Ecuador. An account of these introductions is given in 

 a pamphlet entitled ' 'Millions and Mosquitoes," by H. A. Ballon, issued 

 in 1908 by the Imperial Department of Agriculture of the West Indies 

 (No. 55). In August, 1905, a number of fish were sent to Antigua in a 

 kerosene tin. They arrived in good condition and were kept in a tank 

 at the botanic station until they had sufficiently increased to be dis- 

 tributed. They were liberated in several ponds and streams and 

 increased so rapidly that the country board of health undertook the 

 work of stocking all the ponds and streams of the island. Three 

 years after the first introduction all of the more or less permanent 

 water of Antigua had been stocked, and Mr. Ballon states that many 

 planters and others have commented on the apparent abatement of 

 the mosquito nuisance in many localities. At St. Kitts the intro- 

 duction was equally successful, but the local government did not take 

 up the distribution of the fish as in Antigua. In Jamaica they were 

 established with good results. '' Millions" may be fed in captivity 

 on mosquito eggs and larvae, on raw beef or hard-boiled eggs, upon 

 small insects of any kind, and even upon corn meal. They are 

 readily transported short distances in a kerosene tin with no other 

 preparation than a wire netting arranged near the top to prevent 

 the fish from being thrown out if the water is splashed about. These 

 fish have been introduced at the Isthmus of Panama. 



FISH IN GERMAN EAST AFRICA. 



Mr. J. Vosseler, in an article entitled 'Tische als Moskito-Vertil- 

 ger,"*^ gives an interesting account of some experiments with 

 mosquito-feeding fishes in German East Africa. He discusses the ques- 

 tion quite as authoritatively as does Mr. Seal, already quoted, and 

 brings out the point that on account of the great physical and chem- 

 ical differences in the water inhabited by mosquito larvae the selection 

 of suitable species of fish is made difficult by several restrictions. 

 He states that the shallow shores of rivers or large lakes can be ex- 

 cluded from consideration, since the young of most species of fish 



a Published in Der Pflanzer. Ratgeber fiir Tropische Landwirtschaft, for June 13, 

 1908, vol. 4, No. 8, pp. 118-127. 



