PROTEOSOMA. 249 



species occurring in birds. The latter recognizes nine species 

 of avian Plasmodia, and divides them into three groups 

 according to their morphology, as follows : — 



(1) Spheroidal gametocytes ; nucleus of the parasitized 

 cell displaced by gametocytes and adult schizonts (P. prsecox 

 with pointed pigment and P. cathemerium with rod-shaped 

 pigment in the gametocytes). 



(2) Elongate gametocytes, spheroidal schizonts ; nucleus 

 of the parasitized cell displaced by schizont and sMghtly by 

 gametocytes (P. elongatumj. 



(3) Elongate gametocytes ; nucleus of the parasitized 

 cell never displaced. This may be divided into two sub- 

 groups : 



(a) Adult schizonts small and quadrangular (P. rouxi 



with four merozoites ; P. tenue with 4 to 8 merozoites). 



(b) Adult schizonts circumscribe the nucleus of the para- 



sitized cell (P. circumflexum and P. fallax). 



Coatney and Roudabush (1936) give a list of malarial 

 parasites with their hosts, without expressing any opinion 

 about the number of valid species. De Mello (1937 a) considers 

 the scheme proposed by Giovannola as premature, and refers 

 to his description of P. centropi, which combines certain 

 characters of all the three groups. 



Buxton (1935) has shown that if females of Culex fatigans 

 are infected with Proteosoma, deaths occur earlier than in 

 controls, and thinks it due to the invasion of the wall of the 

 mid-gut by the ookinete. 



Wolfson (1936) was able to transmit bird malaria by the 

 intravenous injection of sporozoites. The salivary glands 

 of Culex pvpiens infected with P. prsecox were dissected out 

 and the contents placed in a solution of 1 per cent, sodium 

 citrate in 0-7 per cent, sodium chloride to which one drop 

 of sterile bovine serum per c.c. was added. Canaries were 

 injected intravenously with 150 mgm. of the solution, and two 

 out of the three birds acquired an infection. 



211. Proteosoma centropi (de Mello). 



^Plasmodium centropi, de Mello, 1937 a, p. 97. 



Gametocytes spheroidal or crescent-shaped ; nucleus of 

 the parasitized cell always displaced ; pigment granular 

 or rod -shaped. 



Remarks. — Full description of this species has not yet been 

 published. According to de Mello (1937 a) the species com- 

 bines the characters of all the three groups of Giovannola's 

 classification as given above. 



Habitat. — Blood of Centropus sinensis parroti Stresemann : 

 Portuguese India. 



