Mature housefly larvae sprayed vifith wettable DDT were fed to 

 largemoutn black bass averaging Zi.$ mm., in lengtn that were isolated 

 individually in 5- by 11-inch roiind battery jars containing 4 inches 

 of vrater. Some of the bass refused the sprayed insects and were 

 eliminated from the test. Eleven bass devoured three or more treated 

 lajrvae (enough to cause marked distension of the stomach) in 2 days. 

 These fish were used in the test. The average temperature of the 

 water in the jars was 69° F. Five bass that ate A, U, 5, 7, and 9 

 treated larvae died 5, 10, 9, 10, 13, and 9 days, respectively, af- 

 ter feeding; only two fish exhibited symptoms typical of DDT poison- 

 ing. Six bass that took 3, 3, 5, 5, b, and 7 treated larvae, re- 

 spectively, survived. Of five control fish tl-iat consumed an average 

 of 21 untreated maggots over a period of 16 days, one died. Although 

 tne fish were proffered all the larvae they would eat, those given 

 untreated larvae ate by far the most. Fish eating poisoned insects 

 were variously affected but significant numbers survived the test. 



Nine largemouth black bass of the same size as those in the 

 preceding experiment were fed maggots sprayed with wettable DDT. 

 Those fed 3, 5, 6, and 7 sprayed larvae, respectively, died within 

 18 hours, and two eating -8 larvae each died before the end of the 

 second dayj others eating 8, 8, and 9 treated larvae survived the 

 10-day test, as did the control bass that consumed 13 untreated 

 larvae each. 



Twenty-six largemouth black bass averaging 50 mm., in length 

 were isolated individually in battery jars . One-half of them were 

 fed mature housefly larvae sprayed with wettable DDT, and one-half 

 were fed larvae sprayed with DDT in oil (formula 2). Five bass were 

 placed in individual jars as controls. The water temperature aver- 

 aged 71° F. The experiinent was terminated after 7 days. Twenty of 

 the 26 fish receiving sprayed larvae died. Of the 20, 9 had eaten 

 lairvae sprayed with tne DDT suspension and 11 had eaten larvae 

 sprayed with the DDT solution. The fish in the controls ate an aver- 

 age of 7 larvae each in a single feeding as compared with an average 

 of 9 each for the bass receiving the suspension- treated larvae and 

 4»5 each for the oil-treated larvae. Great variation occurred when 

 the numbers of treated larvae eaten were compared with survival 

 time in days. Bass tnat had eaten 9 to 14 suspension- treated 

 larvae survived, while others that had consumed fewer larvae died 

 within 1 to 7 days. Of the four bass that ate 4 larvae each treated 

 with DDT oil spray, two were living 7 days later. Most of those that 

 ate from 5 to 8 treated larvae died within 12 hours. The fish in the 

 controls survived. 



