ENDOPARASITA : SPOROZOA. 857 



Individual forms. Peridinium stygium, Joseph, c Grotten-Infusorien,' Z. A. ii. 

 1879, p. 114; Ceratium hirundinella, Blanc, A. N. H. (5), xvi. 1885; Glenodinium 

 cinctum, marine forms, affinities, Butschli, ' Einige Bemerkungen,' &c., M. J. x. 

 1885 ; affinities, &c., Klebs, Biol. Centralblatt. iv. 1884-5. 



Fission, Bergh, Zool. Jahrbucher (Spengel), ii. 1886. Phosphorescence, Id. ibid, 

 p. 83. 



(iv) Cystoflagellata. Noctiluca, Butschli, op. cit. supra, p. 1030 ; Id. M. J. x. 

 1885, pp. 562-73; Allman, Q. J. M. xii. 1872 ; Cienkowski, A. M. A. vii. 1871 ; ix. 

 1873 ; Giglioli, Atti R. Accad. Torino, v. 1870 ; Pouchet, Journal de 1'Anat. et de la 

 Physiol., xix. 1883, pp. 436-8 ; Robin, ibid. xiv. 1878; von Stein, Organismus der 

 Infusionsthiere, iii. pt. 2, Leipzig, 1883, p. 26; physiology, Vignal, Arch, de 

 Physiol. norm, et pathol. (2), v. 1878. Leptodiscus, R. Hertwig, J. Z. xi. 1877. 



ENDOPARASITA. 



Protozoa, in which the organism is either devoid of all special organs 

 of locomotion or is provided with slowly changeable pseudopodia ; nu- 

 trition takes place solely by absorption ; endoparasitic in all stages of life. 



There is one class the Sporozoa. 



CLASS SPOROZOA. 



Endoparasitic Protozoa, rarely motile, reproducing by spores which are 

 usually provided with an envelope (chlamydospores), and are seldom naked. 

 The spores give origin in turn to a variable number of germs, sporozoites or 

 falciform bodies. Conjugation may take place, but as a rule is a mere juxta- 

 position of two or more individuals. 



There are four sub-classes, the Gregarinida, including the Coccidiidae, 

 the Amoebosporidia, Sarcosporidia, and Myxosporidia. 



(i) Gregarinida. The Sporozoa contained in this sub-class are, with 

 few exceptions, in their early stages intracellular parasites. The Cocci" 

 diidae are sometimes found in the connective tissues, but as a rule remain 

 within the cell-host until encystation takes place. The other Gregarinida 

 quit it at a certain period of growth and enter either the coelome or the 

 cavity of the digestive tract. 



The Coccidiidae are round or oval in shape, and in the adult condition 

 motionless ; they are mostly minute in size, but range from '025 up to 

 I mm. in the Klossia of the Cephalopoda. The other Gregarinida are 

 usually elongate, very rarely globular (Adelea\ and are often flattened. 

 An anterior extremity is distinguishable, and may be furnished with 

 organs of adhesion. The majority are small, -001 --02 mm. in length ; some 



