152 



THE AMERICAN MONTHLY 



[August, 



As to parasitic diatoms, we are 

 hardly prepared to believe that 

 diatoms can grow as parasites, in 

 the sense of deriving their nourish- 

 ment from the plants to which they 

 are attached. 



We cannot approve of the use of 

 the term parasite, in the sense which 

 Prof. Brun seems to have applied 

 it in the above translation. 



Classification of the Protista.* 



BY ERNST HACKEL. 

 [Translated by Henry M. Douglas.] 



Class I.— MONERA, Hackel. 



Organisms without organs. The 

 entire body of one of these most 

 simple organisms, consists of noth- 

 ing more than a bit of plasma or 

 primitive jelly, an albuminoid com- 

 pound, not differentiated into pro- 

 toplasm and nucleus. Every moner 

 is, therefore, a cytode, but not a 

 cell. Form mostly indefinite, with 

 shifting projections. Movement 

 sometimes by lobe-feet, sometimes 

 by foot-feet, sometimes by false- 

 feet. Nourishment taken in various 

 ways. Reproduction asexual, by di- 

 vision, budding, or formation of 

 spores. Life in water, mostly in 

 the ocean, also parasitic in other 

 organisms. 



Order 1. Lobomonera, H. Mon- 

 era of varying, indetinite form, 

 moving by lobe-feet (lobopodia) — 

 blunt, linger-like projections, most- 

 ly without branches, as in amoebse. 



Genus : Protammha {primitiva, 

 aquilis, etcX 



Order 2. Rhizomonera, H. Mon- 

 era of indefinite, changing form, 

 moving by root-feet (pseudopodia) 

 — long, fine, thread-like projections, 



* [In publishing this classification of the 

 Protista, it isbelieved that it will be of no 

 little value to students of the minute organ- 

 isms. It is a classification with which English 

 readers are not generally familiar, and for 

 this reason it will doubtless prove to be of 

 interest. — Ed.] 



generally branched and coalescing 

 into a net- work, as in the Rhizc ''' 

 pods. 



Genera : Protomyxa {auran- 

 tiaca) ; Yampjjrella {spirogyra) / 

 Bathyliuti {Ildckelii). 



Order 3. Tachymonera, H. 

 (Synonyms : Schyzomycetes, Bac- 

 teria.) Monera of definite form, 

 mostly staff-shaped or thread-like, 

 whose rapid tumbling or swinging 

 motions are produced by extremely 

 fine lashes {jlagella\ as in the lash- 

 swarmers {Flagelleta). Reproduc- 

 tion asexual, mostly by cross-di- 

 vision. Produce decomposition and 

 putridity of the organic fluids in 

 which they live. Probably the cause 

 of many diseases. 



Genera : Bacterium (monas) ; 

 Vibrio (lineola),' Spirillum (tremu- 



Class II.— LOBOSA, H. (Syno- 

 nym ; Amoebina, Rhizopoda, In- 

 fusoria, Protoplasta). 



One-celled organism (rarely syn- 

 cytia) whose cell-body is sometimes 

 naked (Gymonolobosa), sometimes 

 partly hidden in shells of various 

 forms (Thecolobosa). Movement by 

 lobe-feet (lobopodia) which appear 

 and disappear at various places 

 on the surface. The nourishment 

 is surrounded by these lobe-feet 

 and pressed into the cells. The 

 ]3rotoplasm-body of the cell is 

 frequently separated into a light- 

 colored, firmer, cortical stratum 

 (exoplasma), and a dark, fine- 

 grained, softer medullary stratum 

 (endoplasma). Often it contains 

 one, or several contractile vesicles 

 (vacuoles), sometimes lasting, some- 

 times changeable. The nucleus is 

 usually simple ; rarely there are 

 several present. Reproduction as- 

 exual, mostly by division, more 

 rarely by budding, or spores. 



The Lobosa live mostly in water, 

 rarely in the earth, or parasitic in 

 other organisms. 



