1899] MICROSCOPICAL JOURNAL. 319 



weather it decimates these insects. I believe that I suc- 

 ceeded in reducing" the numbers of flies in my house by- 

 placing- bodies of some dead from Empusa in a suitable 

 cage. I then introduced many healthy ones. In a few days 

 these became infected, and I let them out in order to com- 

 municate the disease to others. The result was that the 

 walls of the rooms were soon covered by flies dead from 

 the Empusa disease. Mr. A. D. Michael, F. R. M. S., 

 etc., if I remember rightly, once told me that it was his 

 custom to style the common house-fly a "menagerie in min- 

 iature," because of the number of parasites to which it 

 acts as host. — H. A. Cummins, Major R. A. M. C, 29 

 Nightingale Place, Woolwich. — In Science-Gossip. 



NEW PUBLICATIONS. 



Mr. J. J. Browning's Catalogue. — Mr. Browning's cata- 

 logue contains many things of interest to microscopists. 

 His micro-spectroscopic apparatus is well-known and re- 

 quires no detailed notice here, but amongst the now numer- 

 ous pocket aplanatic lenses in the market we may mention 

 his Platyscopic lenses which were amongst the earliest in 

 the field, and still hold their own. A useful novelty is Mr. 

 Browning's small micro-camera, concerning which we 

 hope to give our readers further information after a prac- 

 tical trial of its efficiency. Amongst microscopes we may 

 mention the "Iris," fitted with sliding coarse adjustment, 

 micrometer screw fine adjustment, draw-tube, diaphragm 

 plate, and tube for sub-stage apparatus. 



Zeiss' New Catalogue.— Carl Zeiss' Catalogue for 1898 

 is worthy of the reputation of the firm. Beautifully print- 

 ed and bound, excellently arranged, and completely illus- 

 trated, it is more than a catalogue in virtue of the practi- 

 cal explanatory remarks interspersed in the text. Of the 

 eminence of this firm, pre-eminent as makers of the famous 

 apo-chromatic objectives, it is unnecessary to speak, but 

 their catalogue gives detailed information with regard to 

 their stands, objectives, eyepiaces, and accessories, and 

 should be in every worker's hands. 



