1880.] 



MICKOSCOPICAL JOURNAL. 



153 



Order 1. Gymnolobosa, H. 

 Lobosa with naked, soft body, with- 

 out shell. 



Genera : AmcBba {priiiceps ) / 

 Podostoma {filigerum); Petalopus 

 {dvffktens). 



Order 2. Thecolobosa, H. (Syn- 

 onyms : Lepamoebae, Arcellinse, 

 Amosbse, Cataphractse). 



Lobosa with a shell or cell-mem- 

 brane, by which the soft body is 

 partly covered. 



Genera : Arcella {vulgaris)', Dif- 

 jlugia {phlonga) / Quadrula {sym- 

 metrica). 



Class III.— GREGARIN^, Du- 

 four. 



One-celled organisms, or chains 

 of little cells, attached to each other 

 in rows on all sides, by a soft, thick, 

 elastic skin. This cell-membrane 

 is smooth, without any opening, 

 often provided with a hook-shaped 

 attachment. The protoplasm is 

 very elastic and contractile, with 

 numerous granules. The nucleus 

 is large, usually light-colored and 

 spherical, with a lesser nucleus, or 

 nucleolus within. The worm-like 

 movements of the creeping cells 

 take place by contractions of the 

 cortical stratum of the protoplasm, 

 which lies immediately beneath the 

 membrane, and is sometimes dif- 

 ferentiated into filaments resem- 

 bling muscles. All the Gregarines 

 live as parasites in the intestines or 

 body- cavities, more rarely in the 

 tissues, of animals, especially of 

 worms and articulates. 



They live upon the juices of the 

 animal which pass through the 

 membrane into the interior of their 

 bodies by endosmosis. Reproduction 

 asexual, by division or by spores ; in 

 this case a single greparine, or sev- 

 eral Gregarines coalescing, form 

 themselves into a ball, and become 

 surrounded with a capsule. The 

 nuclei then disappear, and the pro- 

 toplasm breaks up into numerous 



ferm-cells or spores (Porospermese, 

 'seudonavicellse). Afterwards a 

 moner comes out of every cell, and 

 by the formation of a nucleus, 

 changes to an amoeba; when the 

 latter covers itseK with a membrane 

 it becomes a Gregarine. 



Order 1. Monocystida, Stein. 

 One-celled Gregarines. 



Gregarine body a simple cell, with 

 a single nucleus. 



Genus : Monocystis {agilio). 



Order 2. PoLYCYSTroA, H. Many- 

 celled Gregarines. 



Gregarine body, a chain of two 

 or three cells (rarely more) strung 

 together, each cell with a nucleus. 



Genus : Didymophes {paradoxa). 



Class IV. — FLAGELLETA, 

 Ehrenberg, (Synonym : Mastigaria.) 



One-celled organisms, more rarely 

 caenobia or cell masses, of few or 

 many loosely united cells, moving 

 by one or more flagella — ^long, 

 thread-like continuations of the pro- 

 toplasm, which swing here and 

 there like a whip-lash — cell-body 

 sometimes naked, sometimes en- 

 closed by a sheath having an open- 

 ing from which issues the flagellum. 

 The flagellates seldom grow attached 

 to objects in the water, usually they 

 swim free. In many of them, rest- 

 ing and moving conditions alternate. 

 Propagation takes place by di- 

 vision, chiefly during the resting- 

 state. ^Nutriment is assimilated 

 sometimes by absoi-ption (endos- 

 mosis), sometimes through a cell- 

 mouth (cystostoma). Reproduction 

 asexual, generally by division ; more 

 rarely by budding or by spores. 

 Indications of asexual distinction 

 are observed in certain forms (Yol- 

 vocinse). 



Order 1. Nudoflagellata, H. 

 Naked flagellates. Flagellates with 

 naked cell-body without a chaplet 

 of cilia. 



Genera : Euglena {viridis); As- 



