6 Psyche [February 
degenerating cells, but here the crystals are formed within the 
nuclei instead of within the cytoplasm. 
Normal blood cells in the early stages of disintegration show 
distinct granulations and also small highly refractive greenish 
crystals within the cytoplasm (PI. I, fig. 7). The nucleus does not 
show any changes till rather late. In a few days the cytoplasmic 
crystals become more and more numerous and likewise grow in * 
size (Pl. I, fig. 8). Still later they reach the size of 5 and 6y 
and assume a shape very closely simulating polyhedra. In a few 
days more the cells disintegrate, completely liberating granules and 
crystals (Pl. I, fig. 9). Some of these liberated crystals measure 
15u or more in diameter (PI. I, fig. 10). Millon’s reagent demon- 
strates their protein nature and I believe that they are similar in 
many ways to the polyhedra. Of course, the composition of the 
polyhedra is different, since they are formed within the nuclei 
under pathological conditions, but what I wish to emphasize is 
that insect tissue has a normal tendency towards crystalline dis- 
integration. Is it, therefore, so surprising to find crystals (poly- 
hedra) within the degenerating nuclei in a series of insect diseases? 
LITERATURE List. 
Goldschmidt, R. °15. Some Experiments on Spermatogenesis 
in Vitro. Proc. Nat. Acad. Sci., Vol. I, p. 220. 
Glaser, R. W. 715. Wilt of Gipsy-Moth Caterpillars. Journ. 
Agric. Research, Vol. IV, No. 2, pp. 101-128, 4 plates, 
17 figs. 
Glaser, R. W. and Chapman, J. W. 7°16. The Nature of the 
Polyhedral Bodies Found in Insects. Biol. Bull., Vol. XXX, 
No. 5, pp. 367-384, 3 plates, 6 figs. 
Lewis, M. R. and Robertson, Wm. R. B. ’16. The Mitochondria 
and Other Structures Observed by the Tissue Culture 
Method in the Male Germ Cells of Chorthippus curti- 
pennis Scudd. Biol. Bull., Vol. XXX, No. 2, pp. 99-114, 
5 plates, 51 figs. 
