GREGARINIDA. 
Prot, 33 
tinction between the Diclymophyidcc and GregarinidcCy s. str., is of sub- 
ordinate importance. He has found a form which unites Monocystidce 
and GregarinidcHy being monocystid when young, and having several seg- 
ments later. His classification is as follows : — 
I. Gregarinida Isoplasta (Cystoplasta, Gabriel, pt.). 
Gregarine-germs and Myxomycete-forms originate simultaneously 
from the body mass. 
II. Gregarinida Proteroplasta {Acystoplasta^ Gabriel). 
The soxually-mature individual is differentiated into a Myxo- 
mycete-plasmodium, from which the Gregarine-germs arise. 
III. Gregarinida Hysteroplasta {Cystoplasta^ Gabriel, pt.). 
The Gregarine-germs appear first, and the Myxomycete-forms 
develop from them. 
Schneider, (40) p. 388, arranges the Coccidia (including the new forms 
described below), for convenience as follows, but does not intend the 
arrangement to represent a formal classification ; — 
Tribe 1. Monosporece. The whole contents of the cyst are converted 
into a single spore. 
(a) Oligozoic forms ; a definite number of corpuscules in the spore. 
Gen. Orthospora. 
(h) Polyzoic forms : an indefinite number of corpuscules in the 
spores. Gen. Eimeria. 
Tribe 2. Oligosporem. Contents of cyst converted into a number of 
spores, which is constant. 
(a) Disporece. Only two spores. Gen. Cyclosporat Isospora. 
(Jb) I'etrasporem. Four spores. Gen. Goccidium. 
Tribe 3. Polysporeoi. Contents of cyst converted into large Dumber 
of spores. Gen. Klossia, Benedenia, 
Genera, Species, &c., Keperred to. 
Gregarina paradoxa^ Gabriel, (38) p. 671, forms spores without pass- 
ing through a preliminary spherical resting-stage. 
Gregarina hlattarum^ Yon Siebold, (36) p. 385, pis. xx. & xxi. 
figs. 10-13. The conjugating individuals really become encysted together^ 
the process constituting a true copulation ; it commences with the abbre- 
viation of the two individuals ; the conjoined pair tend to move round in 
a circle. The pseudo-navicellm are formed by a process of budding 
taking place over the whole surface of the joint encysted mass ; when 
the individuals are completely fused, the pseudo-navicellse disappear 
from the surface of the cyst. Nuclei are to be detected in young pseudo- 
navicellm, but they differ widely from those of the un-encysted animals 
in their smaller size'and in the absence of nucleoli ; they appear to bo 
developed from a zone of free nuclei, found in the peripheral proto- 
plasm of the cyst. The sporoducts are developed from a clear patch of 
protoplasm which appears in the outer part of the contents of the cyst 
Each really consists of direct prolongation inwards of the innermost 
envelope of the cyst ; it becomes surrounded with a finely granular and 
