285 



The cheap arseuite referred to is a mixture of 1 pound of the commer- 

 cial white arsenic to 2 pounds of lime, made by boiling- them toj^ether 

 for half an hour in 2 to 5 gallons of water, and then diluting to the re- 

 quired volume, say 100 gallons. 



THE CORN ROOT APHIS. 



As Article XII, Vol. Ill, of the Bulletin of the Illinois State Labora- 

 tory of Natural History, Dr. Clarence M. Weed publishes his " Sixth 

 contribution to a knowledge of the life history of certain little-known 

 Aphididie,'' giving in this seven-page instalment a partial account of 

 the biology of the Corn Koot Aphis {Aphis maidis Fitch). He estimates 

 that there is no connection between the root and aerial forms of Aphis 

 maidis and gives a summary of the life-history of the former, describing 

 for the tirst time the wingless male (taken in copula witli an oviparous 

 female) and the egg. To consult this series of six contributions which 

 Dr. Weed has now imblishedthe student will have to examine two num- 

 bers of " Psyche," two bulletins of the Ohio Agricultural Experiment 

 Station, one number of Insect Life and one number of the Bulletin 

 of the Illinois State Laboratory, a fact which is to be regretted. 



3I0SQUIT0 LARV^ AS SUPPOSED INTERNAL PARASITES. 



The idea that the larvfe of the mosquito may occasionally become true 

 internal parasites of man has been brought forward by an Italian author, 

 E. Tosatto, and has been adopted by Prof. R. Blanchard in the second 

 volume of his " Traite de Zoologie Medicale" (Paris, 1890). The matter 

 would hardly deserve mention were it not stated in a general work of 

 the high character of Blancbard's, but the fear lest it should become 

 adopted by other authors of books of reference has induced Dr. Eugenio 

 Ficalbi to carefully revie^v the evidence brought together by Tosatto 

 in a recent number of the Bullettino della Societa Entomologica Ital- 

 iana.* Dr. Ficalbi was not contented with showing the weakness of the 

 evidence ui^on which Tosatto founded his claim, but tested the matter 

 by himself swallowing at different times eggs, larvj« in all stages, and 

 pupie of the mosquito. He adds: " It is useless to say that I have di- 

 gested them all completely without being in the least disturbed and 

 without inducing any parasitism." (" Inutile dire die ho digerito com- 

 pletamente tutto cio, senza provare mai il minimo disturbo esenza andare 

 incontro a parassitismo,") The author does not deny that Tosatto tbund 

 the mosquito larva? in the f;eces of his patient, but explains this on the 

 ground that the fieces had been diluted with water which contained 

 larvai or else the receptacle had been rinsed with water infested with 

 larvjB. 



* Bullettino della Societa Eutomologica Italiana. Anno 22. (Fireuze 1891) pp» 

 227-230. 



