402 The Schizogregarines 
Of the following species, occurring in crabs, the schizogonic phases 
only are known. 
Parasite 
Habitat 
Host 
Aggregata portunidarum, Frenzel 
Body cavity 
Portunus arcuatus 
Carcinus maenas 
A. coelomica, Leger 
9 9 
55 
Pinnotheres pisum 
A. vagans, Leger and Duboseq 
9 9 
5 5 
Eupagurus prideauxi 
A. inachi, G. Smith 
99 
55 
Inachus dorsettensis 
Inachus scorpio 
Aggregata sp., Leger and Duboseq 
9 9 
55 
Pachygrapsus marmoratus 
VIII. Classification. 
(a) Previous Glassifications. 
The origin of the name Schizogregarinae (Le'ger, 1900) has already 
been set forth in an earlier portion of this paper (p. 370). Minchin, in 
his article on the Sporozoa (1903), adhered to the classification as set 
forth by Leger, but included Gonospora longissima in the Eugregarines, 
its original position. Caullery and Mesnil in 1898 had found merozoites 
in the gut of Dodecaceria concharum, a Polychaete which harboured 
the Gonospora, and Leger had suggested that Gonospora was possibly 
a Schizogregarine. Caullery and Mesnil associated the merozoites found 
by them with Gonospora, but in 1907 the question of the true adult, to 
which these merozoites belonged, was reopened by Brasil. The latter 
declared his belief that they were stages, not in the life-history of 
Gonospora longissima, but, rather, were part of the life-cycle of Seleni- 
dium echinatum, which also was a parasite of the gut of Dodecaceria. 
The question of the systematic position of Gonospora was incorporated 
by Brasil in an account of a new Selenidium, S. caulleryi, which he had 
discovered, and in his paper (1907) he advanced a new classification of 
the Schizogregarines. This was the first attempt to classify the Schizo¬ 
gregarines on a broad scale, and definitely introduced, in the Selenidiidae, 
forms with intraepithelial schizogony. 
In the first family Brasil placed Schneider’s genus Opliryocystis, and 
retained to some extent the historic name by styling the family the 
Amoebosporidiidae. Schizocystis he included with Opliryocystis in this 
family, in which he also placed Eleutheroscliizon. 
Brasil’s second family was the Selenidiidae , marked by constancy of 
body-form and the presence of contractile myonemes on the body of the 
parasite. 
