H. B. Fantham 
403 
The much discussed Aggregata (Eucoccidium ) which sporulates in 
the gut wall of the cuttlefish and octopus, while its schizogony occurs 
in the crab, was placed by Brasil, on account of its widely different 
mode of life, in a separate (third) family, the Aggregatidae. 
Quite recently, in July 1908, the paper of Leger and Duboscq on 
the Aggregatidae appeared, following on a long paper by Moroff. 
In this, Leger and Duboscq propounded a new classification of the 
Schizogregarines, based on the fact that in Ophrgocgstis two gameto- 
cytes give rise only to a single, octozoic spore. Ophryocystis is 
therefore placed in the subdivision Monospora, the remaining families 
being placed in the Polyspora, since, in the latter, two gametocytes 
associate, encyst and give rise to many gametes, each of which produces 
octozoic spores, as in the Eugregarines. 
Leger and Duboscq’s classification, including Eleutheroschizon and 
Siedleckia, appears thus in tabular form: 
{ Monospora. Ophryocystidae.. .Ophryocystis, Eleutheroschizon. 
tSchizocysticlae...Schizocystis, Siedleckia. 
Polyspora i Selenidiidae.. .Selenidium. 
''Aggregatidae. ..Aggregata. 
In this classification the name Amoebosporidia is finally discarded, 
but unfortunately Ophryocystis and Schizocystis, which are alike in 
possessing extracellular schizogony, are widely separated. 
The following important points in connection with Schizogregarines 
need to be considered in any scheme of classification : 
(1) The extracellular character, as regards the tissues of the host, 
of Ophryocystis and Schizocystis. 
(2) The intra-cellular character of the schizont in the Selenidiidae 
and the Merogregarinidae. 
(3) The fact that the schizogony of the Aggregata occurs in a 
different host (Decapod Crustacean) from its sporogony, which takes 
place in a Cephalopod Mollusc. In the words of Leger and Duboscq, 
Aggregata is a Gregarine which is digenetic as regards phases of its 
life-cycle, and heteroi'c as regards its hosts. 
(/3) A New Glassification. 
We must not overlook the uncertainty which still prevails regarding 
the phenomena of fertilisation in the so-called Eucoccidium, as described 
by Moroff (1908) on the one hand, and Siedlecki (1898) on the other, 
and its bearing on the position of Aggregata (Eucoccidium ). Taking 
