302 E. A. MINCHiN. 



Schueideri, from Holothuria poli and impatiens, which 

 is characterised as follows: — ''Has a general facies and a 

 method of sporification similar to that of the preceding^ 

 species^ differs from it in being smaller and much less resis- 

 tant to the direct action of sea water, while C. holothurise 

 can stand it much longer." I should think it probable that 

 no new species of animal which has been described within the 

 last fifty years has been founded on such a meagre and insuf- 

 ficient diagnosis as this — without, moreover, any figures. 



Since one of these Gregarines possesses a caudal process to 

 the spore and the other not, it is obvious that this caudal 

 process cannot be used for classification. This at once 

 sweeps away the genus Urospora for these species, and also 

 Mingazzini's arguments for placing them in the family 

 Syncystidse. 



The genus Syncystis was founded by Aime Schneider (7) 

 in 1885 for a Gregarine found by him in the fat bodies of Nepa 

 cinerea. The body is pear-shaped or spherical, and in the 

 latter forms Schneider was unable to see " la moindre trace 

 d'une division du noyau " (p. 92). Two such individuals fuse 

 before eucystment, as occurs in many, if not all Gregarines. 

 The sporulation is not complete, since a central mass of proto- 

 plasm remains over. The spores are oval, and usually have 

 four bristles at each end ; they contain eight sporozoites, each 

 with a nucleus and nucleolus, '' arranged obliquely, giving 

 lines which cross one another from one face of the spore to 

 the other; at the centre a nucleus de reliquat " (p. 94). 

 From figs. 21, 22, and 23, pi. xxiii, it can be seen that the 

 nucleus of the sporozoite is placed in its centre. 



If this summary of Schneider's description of Syncystis 

 be compared with that given above of the Holothurian Gre- 

 garines there only appears to be one point common to the 

 two — the formation of eight sporozoites in the spore, which 

 occurs also in the Monocystis of the earthworm, and in 

 Clepsidrina ovata, a Polycystid (Schneider, ' Tablettes 

 zoologiques,^ i, pp. 25 — 28, pi. xi), as well as in Coleophora 

 hcros (Schneider, op. cit., p. 98, pi. xxv, figs. 11 — 13, a), &c. 



