1924 ENTOMOLOGICAL SOCIETY 71 



On the 29th of September it was discovered that twenty of the original 300 

 chicks had previously been in contact with adult fowls and these were subse- 

 quently placed in contact with the entire number which resulted in all of them 

 becoming infested with head lice. This unfortunate circumstance necessitated 

 treatment of all controls, blue ointment being used for the purpose. The oint- 

 ment used was the ordinary commercial preparation diluted to half normal 

 strength. One application only was necessary to clean up the infection and no 

 untoward effects were observed in any of the treated birds. 



Without burdening you with full details of weighing, feeding, etc., it may 

 be sufficient to state that our results were somewhat similar to the first experi- 

 ment, the mortality rate being average and practically the same for both pens. 

 The remaining 250 chicks were kept under observation until late in November 

 and during this period no inordinate death rate was noted. Upon actual count 

 some individual chicks were found to harbour over one hundred adult lice and 

 as time progressed and the chicks grew, the numbers diminished until only a few 

 lice could be detected. 



References to the head louse of chicks are mostly contained in popular 

 bulletins and check lists of animal parasites, and it is therefore little to be won- 

 dered at that this parasite has been given a pathological role to which it is little 

 entitled, this impression being based upon the personal observations of practical 

 poultrymen little familiar with the many factors contributing to the heavy death 

 rate amongst early-hatched chicks. When it is considered that out of every four 

 eggs incubated, an average of only one chick is raised to maturity, and that in 

 many cases of early spring hatching by artificial methods, the mortality amongst 

 hatched chicks may run well over 50 per cent, during the first ten days of life, 

 due to such conditions as aspergillosis or brooder pneumonia, white diarrhoea, 

 defective incubation, etc., we have little reason for holding head lice responsible 

 for the heavy mortality during this hazardous period. Admittedly, parasitism 

 of any nature or degree must be considered in relation to susceptibility to disease, 

 for undoubtedly a lowered resistance resulting from a heavy infection tends to a 

 fatal issue. In many cases, however, a heavy degree of infestation is an index 

 of lowered resistance from debility and faulty metabolism, or in the case of fowls, 

 from confinement, overcrowding and a withdrawal of the natural means of 

 defense, and in such instances, the presence of parasites may be regarded as the 

 result and not the cause of impaired vitality. 



While our investigations concerning this parasite are limited, sufficient 

 experimental work has been done to satisfy the writer that the head louse of 

 chickens is a much maligned parasite from whose passivity has been created a 

 role of activity which from personal observation or analogy I judge to be little 

 warranted. 



INSECTS OF THE SEASON IN QUEBEC IN 1923 

 Georges Maheux, Provincial Entomologist, Quebec 



The summer of 1923 has been a very heavy season for insect pests, and 

 damages, as a whole, easily double last year's figure. Sometimes it appeared as 

 if insects of normally very little importance thought it compulsory to show, in a 

 brighter light, their noxious power. This explains why the ordinary short list 

 of important pests is so greatly extended. 



