— 172 — 
other portions of the tropics (1). Girardinus peciloides measures 
about 35 m. in length; it frequents water too shallow for larger 
fish; is viviparous, and increases very rapidly. It is closely 
allied to G. versicolor of San Domingo and G. formosus of 
South Carolina and Florida. Mr. BALLOU, after carrying on investi- 
gations extending over a long period, is of opinion that Girardi- 
nus is a very efficient enemy of Mosquitos. He has observed it 
devouring the eggs, larve and pupa of Culex and Stegomyia as 
well as of Anopheles. Instances are quoted of the success of the 
introduction of Girardinus to other parts of the West Indies. More 
recently small consignments of the fish have been forwarded to 
West Africa and India. Somewhat similar small fish known as « top 
minnows » have been utilised to control Mosquitos in the United 
States. In 1905 the U.S. Fish Commission was instrumental in 
introducing a large number of « top minnows » with good 
results from Texas to the Hawaiian Islands. It is probable that 
many other small fish that multiply rapidly would prove of value 
in controlling Mosquitos. The subject is one which is deserving of 
careful attention in all tropical countries. 
(1) Millions and Mosquitos. Pamphlet Series (Imperial Department of Agricul- 
ture), No 55. London, Dulau and Co, 1908. Price : 3 pence. 
