1897J MICROSCOPICAL JOURNAL. 231 



stained on one half of the smear, leaving- the other halt" 

 unstained, in which measurements of a g-iven number of 

 corpuscles, taken as they come, from each part, give iden- 

 tical results. C. M. Vokce. 



Crystals in Blood Corpuscles of Frog. — I have a slide 

 prepared by the process of the late lamented Allen Y. 

 Moore, M. D. The blood was spread on slide, and dried; 

 flowed with aqueous sol. of eosin, and washed; flowed with 

 aqueous sol. of methyl blue, and washed, dried, and moun- 

 ted in balsam. 



The blood of fishes, frogs, and perhaps other reptiles, 

 often exhibits crystals apparently within the corpuscles 

 when simply dried without staining. This has been 

 noticed by many observers. 



These elliptically formed crystals are not in the same 

 plane as the corpuscles, and seem to be on the cover-glass. 

 It is the custom of some to cleanse the covers in an acid 

 solution, and then rinse in alcohol. If this was done, the 

 cause of the crystals being there might be from an insuffi- 

 cient washing after the acid bath. If a few drops of a sat- 

 urated solution of any of the salts in water be dropped 

 into a little alcohol, the salt immediately crystallizes into 

 individual crystals such as are seen in this mount. I have 

 had slides showing crystallization in film so thin as to be 

 seen only by polarized light, which I attributed to an insuffi- 

 cient washing after soaking in a cleansing bath of borax 

 solution ; and I believe that if they had been rinsed in alco- 

 hol it would have produced individual crystals and not a 

 thin film. Thos. J. Bray. 



Larvae of Clothes Moth. — These larvae are very small 

 at first ; the body is white and soft, and seems to need the 

 protection of the tube or case which it builds from the 

 woolen fibres cut small and cemented together. My spe- 

 cimens were taken from a fancy worsted crocheted mat, of 

 no earthly use, and consequently somewhat neglected; the 

 dyed wool as utilized by the insect makes a pleasing object. 

 The six anterior feet of the larvae are strong and can drag 

 the caterpillar and its case along in this fashion : the body 



