24 (88) Society for Experimental Biology and Medicine. 



1. — Hcemoproteus danileivskyi, syn. Halteridium. 



2. — " maccalliuni, n. sp. 



3. — " sacliarovi, n. sp. 



4. — " majoris, Lav. 



5. — " ziemanniyYj&x. 



6. — " rouxii f n. sp. 



Plasmodium vaughani, n. sp., is common in robins ; it re- 

 sembles proteosoma, and may be easily mistaken for the latter. 

 The hyaline body is smaller than that of proteosoma, does not 

 displace the nucleus, contains one large pigment granule, and is 

 readily recognizable by the presence of a large, bright, refractile, 

 colorless globule. It segments and usually forms four cells. 

 Canaries may be infected ; apparently non-fatal. 



Hczmoproteus maccallumi> n. sp., found in mourning doves. 

 Like halteridium, which it resembles, it infects erythrocytes. 

 Grows on one side, or may completely surround the nucleus. 

 The fully developed sexual forms fill and somewhat distend the 

 blood cells. Microgamete formation observed. The infection 

 cannot be transferred by blood injection. 



Hcemoprotcus sacharovi, n. sp. This species, probably first 

 observed by Sacharoff, who regarded it as a " leucocytozoon," is 

 related to that of Danilewsky. Found in young mourning doves 

 and elsewhere. Invasion begins with an infection of very young 

 erythroblasts. As the parasite grows it pushes the nucleus to the 

 periphery, where it is seen in the adult form on the outer edge as 

 a cap, which is but a trifle larger than the nucleus of a red blood 

 cell. The parasite is spherical, male and female forms common, 

 latter predominate ; blepharoplast distinct, adjoining or over the 

 nucleus. Microgamete formation common. Infection not trans- 

 ferable by the blood. 



Hcemoprotetis majoris, Lav. This was found once by Laveran 

 in a titmouse. This species is extremely common in robins and 

 other birds. As with preceding species, invasion at early stage 

 shows infection of very young erythroblasts, the small parasite 

 lying next to the large round nucleus. As the parasite grows it 

 pushes into the nucleus, which becomes crescentic and may almost 

 wholly surround the parasite. The adult sexual forms are large, 

 about 10 to 12 microns in diameter, and are readily recognizable 



