NATURE OF POLYHEDRAL BODIES FOUND IN INSECTS. 381 



selves of the presence of proteins. This protein solution freed 

 from the alkali was now slowly evaporated. On partial evapora- 

 tion, we found beautiful single and double crystals which simu- 

 lated the polyhedra very closely. If the material is evaporated 

 completely it is difficult to find the crystals owing to the presence 

 of coagulated and other protein material which hides them. If 

 one shoots water under the cover-slip, however, the crystals 

 again become visible just as soon as the coagulated sediment 

 softens and becomes transparent. This fact that a coagulated 

 residue remains shows that the entire protein material contained 

 in the original polyhedra is not used during the formation of these 

 new crystals. The majority of the crystals produced in this 

 way simulate polyhedra very closely, but some are rounder and 

 larger. Double forms are very common and are absolutely 

 indistinguishable microscopically from ordinary polyhedra. The 

 staining reactions of the crystals are similar to those of the poly- 

 hedra and Millon's reaction is identical. We have as yet not 

 obtained a sufficient amount of these new crystals to submit them 

 to all of the protein tests applied to the polyhedra. The crystals 

 are not quite as stable as the polyhedra. They seem to lack the 

 more resistant outer layer and therefore are more easily soluble in 

 alkali and other reagents. For this and other reasons we do not 

 claim to have reproduced typical polyhedra after their disintegra- 

 tion, but we firmly believe that the results are suggestive. It 

 seems unreasonable, after submitting proteins to the violent 

 hydrolytic action of both heat and alkali, to expect to reproduce 

 the identical proteins. However, in the material under con- 

 sideration, there seems to be a tendency for this particular 

 protein or group of proteins to crystallize out in the shape char- 

 acteristic of the polyhedra. These observations seem to support 

 our view that the polyhedra are merely degeneration-products 

 and not some inexplicable, unclassifiable organisms as supposed 

 by many workers. An organism certainly could not be dissolved 

 and its original form again reproduced or very nearly reproduced 

 on evaporation. 



So far we are unable to obtain the crystals after the dissolution 

 of the polyhedra at every trial. Out of possibly ten trials, one 

 usually succeeds four or five times. Undoubtedly some condition 



