1895 THE MICROSCOPE 123 



and if not quickly dipped and as quickly rinsed may ruin 

 the plate. With ordinary care there is no danger of 

 this. When the glass is removed from alcohol to plate 

 do not dry it or allow to become dry, but cover imme- 

 diately with the wax solutions. Do not allow the solu- 

 tions to stand after mixing but use immediately. 



While the solutions recommended will work equally 

 as satisfactory on larger glass, the process of applying 

 them must be modified. 



Do Flies Have Teeth? 



By THOS. J. BRAY, 



WARREN, OHIO. 



If any one had asked me this question two weeks ago, 

 I should have replied, " I believe not." Last week, being 

 in Minneapolis, I spent all my spare time in the company 

 of Messrs. H. G. Carter and John Walker, two enthusias- 

 tic amatuer microscopists. There I saw several new con- 

 trivances pertaining to microscopic technique that inter- 

 ested me very much. Mr. Carter has a clever way of 

 making indestructible cell rings, also a very fine trans- 

 parent amber cement, which is elastic, hence very suit- 

 able for ringing mounts. He has recently devised a 

 novel way of preparing the tongues of flies for mounting 

 and an ingenious little instrument by which they are 

 manipulated in the preparation. Mr. Walker has de- 

 vised an animalcule trap or catcher, which is very sim- 

 ple and effective and can be carried in the coat pocket. 



These gentlemen have been giving special study to the 

 mouth parts of flies and they exhibited several slides of 

 this kind which showed very plainly the teeth, of which 

 there are three rows, the back row being the longer and 

 the front row the shorter. Each tooth is "serrated " or 

 notched out on the point with a Y shaped notch. 



To see the teeth, take a clear mount ot the tongue of a 



