632 W. S. PERRIN. 
PLATE 38. 
Fie. 25.—Trophozoite of Pleistophora periplanete showing elongated 
non-nucleated pseudopodium of ectoplasm. Sublimate alcohol and Delafield. 
Fic. 26.—Trophozoite giving off bud. 
Fie. 27.—Nucleus of cell of Malpighian tubule, fixed with hot sublimate 
alcohol, stained Delafield. This figure, with Fig. 15, is inserted for the 
purpose of indicating the size of Pleistophora periplaneta—the nucleus 
measures 16 » in diameter—and showing the drastic effects of fixation by 
drying on such a spherical body as a tissue nucleus (see Fig. 15 as compared 
with Fig. 27). The leaf-like trophozoites are, upon the contrary, well pre- 
served by this method of fixation. 
Fig. 28.—Trophozoite fixed with osmic acid vapour and deeply stained 
with iron hematoxylin. 
Fic. 29.—Trophozoite showing the mucoid masses which occasionally 
occur in the trophozoites. 
Fie. 30.—Pansporoblast with sporoblasts containing a nucleus in the form 
of scattered dots or a reticulum. Stage is slightly antecedent to Fig. 14. 
The residual nuclei are seen as deeply stained masses between the sporo- 
blasts. 
Fic. 31.—Pansporoblast at a later stage. The nuclei of the sporoblasts 
are now in the form of a sphere containiug a central particle. 
Fig. 32.—Still later stage. The nuclei are still more condensed and the 
spore coats are beginning to be formed. 
Fic. 83.—Small pansporoblast with four spores. Stage much later than in 
Fig. 32. A thick spore coat is present and two nuclei, one each side of the 
central vacuole, are to be seen. Magnification 2700/1. 
Fic. 84.—Trophozoite in an early stage of multiple plasmotomy. 
Fic. 35.—Later stage in same process. One bud is just free. 
Fie. 36.—Multiple amitosis; see also Figs. 16—19. 
Fic. 87.—Spores of hitherto undescribed Myxosporidian fixed with sub- 
limate alcohol and stained Delafield’s hematoxylin. 
Fries. 88 to 47.—Series of figures showing the changes in the nucleus in 
the development of the spore from the sporoblast. 
Fig. 38.—Nucleus of the sporoblast as a number of discrete particles. 
Fig. 39.—Nucleus somewhat more condensed than in Fig. 38. Particles 
fewer and larger. 
Fig. 40.—Nucleus of spore in the form of a ring of four chromosomes. 
Fig. 41.—Similar stage. A small vacuole is to be seen in the sporoplasm. 
Fig. 42.—Later stage. Vacuole increased in size. 
