lao 



Notes, Communications and Reviews. 



spread among blood-sucking insects, unless it be possible to 

 distribute the Nosema spores in suitable places where the 

 insects may congregate to drink in moisture. Unlike the 

 species affecting silkworms, it has yet to be proved whether 

 Nosema apis can be transmitted by the queens to the eggs 

 and so produce infected young. So far as is known at present 

 the disease does not seem to affect the brood to any appreciable 

 extent. Chapter XII. deals with the Myxosporidia which are 

 the agents bringing about disease in many species of fishes and 

 also in certain Crustacea. The barbel disease of the South of 

 England is a noteworthy example, as well as the epidemics 



Fig. 4.— Nosema apis; Spores and Spore Formation. 

 (Published by permission of the Authors and Publishers.) 



among trout and pike on the Continent. :' Chapter XIII. is 

 concerned with parasitic Ciliates ; these, however, are seldom 

 associated with serious disease and are of less importance 

 economically than many other groups. Chapter XIV. is 

 devoted to the parasite of nasal polypus in man and to certain 

 common muscle parasites of birds, mice and sheep. The 

 concluding chapters of the book run to twenty-five pages, and 

 contain general remarks on the relations of parasitic Protozoa 



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