28 



The average period of incubation, as shown by the above figures, 

 is nearly seven and a half days under the conditions noted. 



NYMPHS. 



For several hours after hatching the young njmiphs remain closely 

 clustered uj^on the top of the egg batch, with scarcely any perceptible 

 movement. In all cases where the eggs of this species have come 

 under the writer's observation, less than two-thirds of the total num- 

 ber in the batch have hatched, although those which failed to hatch 

 contained nymphs. It was found that, as in many other species of 

 pentatomids, the nymj)hs of the first instar which first hatch begin 

 to feed, after a few hours' quiescence, upon the contents of the 

 imhatched eggs. It is not impossible that some or all of the nymphs 

 thus fed upon were already dead. Some of the n3^mphs which have 

 been observed obtained enough food from the unhatched eggs to pass 

 through the first instar. Others became quite plump by feeding upon 

 the eggs, but fed readily upon fresh cotton leaves when placed upon 

 them. The first molt occurred the seventh day after hatching, and 

 the second molt on the third and fourth davs after the first. It was 

 impossible to give the young insects the attention necessary to breed 

 them to maturity, and all of them died before molting a third time. 



INJURY TO COTTON. 

 Injury to Cotton at Tlahualilo in 1903. 



As stated in the introduction, it was estimated after a personal 

 examination of the dx}^ stalks in the cotton fields at Tlahualilo on 

 March 8, 1904, that an average of 10 to 15 per cent of the cotton 

 bolls were injured by some agency to the point of Avorthlessness. 

 The nature of much of this injury was found to be, to all appear- 

 ances, identical with that resulting from the attacks of the conchuela, 

 as observed in fields of growing cotton at Tlahualilo from August 30 

 to September 8. Concerning some of the bolls, there was more doubt 

 as to the cause of the injury, which consisted in the locks dying after 

 reaching a late stage in their development. The opened bolls showed 

 more or less stained fibers remaining closely matted together, and at 

 the extreme tip noticeably shriveled. In consideration of the possi- 

 bility that this injury was due to a vegetable disease, dry specimens 

 were submitted to Dr. A. F. Woods, pathologist and physiologist of 

 the Bureau of Plant Industry, with a request that they be examined 

 for evidence of trouble of this nature, but it was found that no fun- 

 gous disease could have been responsible for their condition. There 

 being no evidence of a disease of a bacterial or physiological nature, 

 there is but little doubt that the condition described above is due to 



