THE TOP MINNOW, (GAMBUSIA 

 AFFINIS) 



By E. N. Carter, 

 Superintendent, U. S. Fisheries Station, Bullochville, Ga. 



The range of this species of top minnow, Gambusia af- 

 finis, as given in Economic Circular No. 17, of the U. S. 

 Bureau of Fisheries by Mr. Lewis Radcliffe, is from 

 New Jersey to Florida on the east, from Illinois to Louis- 

 iana on the west and thence to the rivers of Texas and 

 Mexico. In size they are from an inch to an inch and a 

 quarter in the males and from an inch and a half to two 

 inches and a half in the females. The adult male is dis- 

 tinguished from the female by the long bayonet-like anal 

 fin of the former. 



They seem to prefer the shallower waters and when ob- 

 served are always in motion, swimming hither and thith- 

 er among the grass and weeds which line the edges of 

 the ponds or streams. They are not so graceful as the 

 young bass or sunfish. The constant motion makes their 

 swimming seem almost laborious, as though impelled by a 

 force over which they have no control. Their small 

 bodies are like animated steel springs and they flip from 

 the net or seine in which they are taken as if snapped 

 from beneath with one's finger. Yet with all their won- 

 derful activity and their ability to survive under the most 

 trying circumstances, they are frail and will stand little 

 handling. Hands off and they will live in cold, spring 

 water and in small pools of very warm water, such as 

 are formed by boot tracks in the soft mud of a pond that 

 has been drained the previous day and left exposed to the 

 sun. 



In his waking hours Gambusia affinis is a constant 

 searcher for food, a habit which makes this insignificant 

 creature a blessing to mankind, at least to that portion 

 of mankind unfortunate enough to dwell where the mos- 



