40 PROCEEDINGS OF THE ACADEMY OF [Jan., 



Fig. 38. — Camera outline. Thionin and acid fuchsin. Mouse 253, 6 hours, 



int. 16. Male. Parasite reduced to its nucleus which shows the nuclear 



net and a large central mass of chromatin. 

 Fig. 39. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 99, 



3 and 6 hours. Male. The parasite, reduced to the nucleus, shows a 



well-developed nuclear net and a basophil karyosome nearly cut into two 



by a cleft,. 

 Fig. 40. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 



9 hours. Male. Parasite reduced to its nucleus, which shows the typical 



net and a large central aggregation in which are five basophil granules. 

 Fig. 41. — Camera outline. Delafield and eosin. Mouse 106, 9 hours. Typical 



male parasite. 

 Fig. 42. — Camera outline. Delafield and acid fuchsin. Mouse 106, 9 hours. 



The figure shows two male parasites lying in adjacent cells of the mouse, 



and it is instructive in that a marked contrast in staining reaction is to be 



seen, the upper cell being acidophil, the lower basophil. 

 Fig. 43. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 99, 



3 and 6 hours. Male, doubtless belonging to the 6-hour period. The 



nuclear net is in the main acidophil, but a portion of it has taken on a sharply 



basophil staining reaction. 

 Fig. 44. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 



9 hours. Male. Shows a typical nuclear net, a large acidophil karyosome 



and a number of basophil granules. 

 Fig. 45. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 



9 hours. Male. The nuclear material is partly acidophil, partly basophil. 

 Fig. 46.— Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 



9 hours. Male. The chromatin is basophil and finely divided. 

 Fig. 47. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 



9 hours. Male. The chromatin is basophil, and occurs as minute granules, 



except for the cluster of larger granules which is presumably derived from 



the karyosome. 

 Fig. 48. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 



9 hours. Male. The chromatin is partly acidophil, partly basophil. 



Fig. 49. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 

 9 hours. The chromatin is basophil and in a state of fine subdivision, 

 except for the central mass which is probably derived from the karyosome. 



Fig. 50. — Camera outline. Thionin and acid fuchsin. Mouse 106, 9 hours. 

 Male. The parasite shows a delicate net provided here and there with 

 basophil granules. 



Fig. 51. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 106, 

 9 hours. Male. The parasite shows a delicate net provided with minute 

 chromatin granules. 



Fig. 52. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 120> 

 IO5 and 17 hours. Male. The chromatin is extremely basophil and the 

 bulk of it is concentrated into round balls. It is impossible to say to which 

 of the two infective feeds this parasite belongs. 



Fig. 53. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 120, 10J 

 and 17 hours. Shows two male parasites lying side by side. Instructive on 

 account of the marked difference in staining reaction. 



Plate IV. — Fig. 54. — Camera outline. Iron hematoxylin and acid fuchsin. 

 Mouse 120, 10§ and 17 hours. Male. The central aggregation consists of 

 sharply basophil substance between which is acidophil material. In the 

 former rounded granules can be distinguished. This central mass is throwing 

 out extensions into the balance of the nucleus where there are aggregates 

 composed partly of sharply black granules and partly of acidophil material. 



Fig. 55. — Camera outline. Iron hematoxylin and acid fuchsin. Mouse 120, 

 IO5 and 17 hours. Male. The chromatin is black in the iron hematoxylin 

 and occurs as minute granules. The general mass is showing a tendency 

 both to form small clusters and to assemble upon the periphery. 



