20 



investigations made on city flies, show that these insects carry both 

 on and in their bodies, very large numbers of bacteria, many of which 

 are derived from faecal material. 



The author gives at some length such evidence as exists as to the 

 period of survival of micro-organisms ingested by the larvae in the 

 adult flv. The evidence as to pathogenic bacilli in this respect is 

 not very conclusive, but it must not be forgotten that under natural 

 conditions, flies which emerge from infected larvae may be able to 

 re-infect themselves if the contaminating organism still survives m 

 material surrounding the pupae. 



The question of the carriage of typhoid fever by flies is discussed at 

 some length. The author is satisfied that flies, if suitable oppor- 

 tunities of visiting infected material occur, may carry and distribute 

 organisms of this type for several days. A lengthy chapter is devoted 

 to summer diarrhoea in relation to flies, and the author says that both 

 the entomological and bacteriological evidence is so suggestive and 

 the disease is of such importance, that an attempt to settle definitely 

 the connection between flies and summer diarrhoea, by experimental 

 preventive measures against flies in a selected area, seems now justi- 

 fiable. Cholera, tuberculosis, anthrax, diphtheria and ophthalmia are 

 dealt with, and the author then proceeds to discuss certain non-bac- 

 terial diseases in this connection, poliomyelitis, small-pox, tropical 

 sore, trypanosomiasis and yaws. 



Another chapter is devoted to the consideration of the part played 

 by flies in the dispersal of the eggs of parasitic worms. The author 

 considers the evidence up to the present as unsatisfactory, but, provided 

 the ova are not too large, flies can ingest them and deposit them 

 uninjured in their faeces in some cases up to the third day at least. 

 The ova may also be carried on their legs or bodies, and thus food and 

 fluids may be contaminated. The question of myiasis is also discussed 

 at some length. 



The concludmg chapters of the book deal with the diseases of flies, 

 their parasites and their enemies, and Howard's list of flies frequenting 

 human faeces is quoted. Measures of control are then discussed, and 

 the final chapter consists of a summary and conclusions. A very 

 complete bibliography, extending over IT pages, closes the book, which 

 contains a great mass of well-arranged information, and constitutes 

 a valuable summary of the whole subject. 



Neish (W. D.). The Tabanidae and Anophelines of Jamaica. — Report 

 of the District Medical Officer, Spanish Toidk Jaitmica, 

 August 1913, 3 pp. 



In a letter from Dr. W. D. Neish, District Medical Officer, Spanish 

 ToAvn, to the Superintending Medical Ofl[icer, the folloAnng list of 

 Tabanidae, so far known to occur in the island is given : — Chrysops 

 costatns, ¥., Lepidoselaga lejndota, Wied., Tabanus alene, Towns.. 

 T. angustifrons. Towns., T. hicididus, Walker, T. obliqiivs, Walker, 

 T. nifiventris. Walker, T. trilineaius, Latr., T. parallehis, Walker. 

 With the exception of Chrysops costatns, all the Tabanidae are 

 exceedingly rare in Jamaica. So far as is known, none transmits any 

 disease. Reference is also made to two species of Aiiopheles. Nothing 

 is known as to the habits of Anopheles veslilijjennis, Dyar and Knab, 



