457 



the various stages of the Ufe-history of all three species is discussed. 

 It has been thought that larvae or adults of G. atrum quickly die when 

 deprived of nourishment ; the author's experiments, however, have 

 proved that young larvae, at least, can exist for several days without 

 food. The general manner of feeding in the case of both larvae and 

 adults is to attack the tender parts of the plant. Observations are 

 recorded on the feeding of 17 larvae on lucerne from the time of 

 hatching to the inactive period before transformation. It is evident 

 from these that during the first half of its existence the larva eats much 

 less than the adult, but later, and particularly during the last few days 

 of its development, it eats considerably larger quantities. On the 

 whole, the adult insect is the greater feeder, its period of activity being 

 longer than that of the larvae. The method of feeding and the amount 

 of nourishment required by adults of G. luteola and A. cdni are very 

 similar ; each hves for two months or more and eats a considerable 

 quantity per diem throughout this period. 



Some account is also given of Meigeniafloralis, the Tachinid parasite 

 of C. atrum [see this Review, Ser. A, vi, p. 171]. 



Feytaud (J.). Recherches sur TEudemis et la Cochylis dans le 

 Bordelais en 1914. — Ann. Service des Epiphyties, Paris, iv (1915), 

 1917, pp. 218-265, 4 figs. [Received 1st September 1919.] 



From a series of observations on Clysia ambiguella and Polyckrosis 

 hotrana in the Bordeaux region in 1914 it was ascertained that 

 mortahty was high in the winter 1913-1914, varying between 75% and 

 93% in 'different locahties. The principal factor was the presence 

 of fungus diseases, which were encouraged by the autumn rains and 

 which killed some 46 to 58% of P. hotrana. Another factor was the 

 activity of Ichnemnonid parasites, causing the death of 13 to 22% of 

 C. ambiguella. The action of cold on hibernating individuals of 

 P. hotrana is discussed. The author is convinced that in Gironde 

 the abnormal cold of the winter 1913-1914 did not diminish the 

 numbers of this moth, but rather encouraged its increase by kiUing 

 off many of its natural enemies. C. ambiguella is known to be 

 naturally more resistant to cold than P. hotrana. 



The value of various insecticide treatments is discussed, the formulae 

 for these being given. Tests made in May and June 1914 on eggs of 

 P. hotrana confirm former results as regards the action of nicotine 

 [see this Review, Ser. A, vi, p. 72]. Positive results were obtained 

 with quinohne 1%, phenic acid 1% and potassiimi sulphocarbonate 

 1%. Pyrethrum powder 2% gave poor results ; sodium sulphoricinate 

 1% and permanganate of potassium 1% gave negative ones. 

 The successful substances apparently killed the eggs immediately by 

 directly arresting the development of the embryo ; pyrethrum, which 

 only prevented development of one-sixth of the eggs, had the same 

 action as nicotine, the larva becoming poisoned at the moment of 

 eating its way out of the egg. The results of various experiments in 

 the field are given. Details of the poison-baits and shelter-traps have 

 already been noticed [see this Revieiv, Ser. A, i, p. 415, iv, pp. 309, 492, 

 V, p. 136, vii, p. 90, etc.]. 



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