378 



GENERAL HISTORY OF THE INFUSORIA. 



characters only — to the presence or absence of locomotive organs, to the 

 characters of those organs, to the nature of the external surface, whether 

 protected by an integument or not, or defended by a lorica, to the general 

 conditions of attachment of fixed forms to other objects, and to the cha- 

 racter of their movements when free. Moreover, his Ciliated Infusoria com- 

 prised not only our group of Ciliated Protozoa, but also the Phytozoa, — the 

 Vibrionia only excepted ; for he made no distinction between organisms moved 

 by a single or few filaments, and those moved by vibratile ciha generally dis- 

 tributed, or associated together in the construction of special locomotive organs. 



In his tabular view, the beings we have brought together under the appel- 

 lation of Cihata are all comprehended in the foui'th and fifth orders of Infu- 

 soria, with the exception of CoUps and the Iclithydina, which, in his opuiion, 

 belong to a type of structm^e differing from all others reckoned by him as 

 Infusoria, in being symmetrical. 



The accompanying outline of this system of Dujardin ^vtU sufficiently illus- 

 trate it at present, without further remarks on the value either of the prin- 

 ciples he has adopted, or of the families and genera he has instituted. 



DUJAEDIJf'S CLASSIFICATION OF CILIATA. 



Order IV. — Cihated animalcules without a contractile integument. All swimmers. 



A. Naked. 



Fam. 11. Enchelyens, without mouth; ciUa disposed without order. 



12. Trichodiens, with the mouth either visible or indicated by a fringe of cilia, with- 



out cirrhi. 



13. Keroniens, with a mouth and a fringe of ciha, together with some cirrhi or 



strong cilia in the form of styles or uncini. 



B. LORICATED. 



Fam. 14. Ploesconiens. Lorica or sliield diffluent or decomposable like the rest of the body. 

 15. Ervihens. Lorica genuine and persistent. A short pedicle. 



Order V. — Ciliated animalcules provided with a lax, reticulated, and contractile integu- 

 ment ; or having theu' ciha so arranged in regular linear series as to 

 denote the presence of an integimient. 

 A. Always free. 



Fam. 16. Leucophry ens, without a mouth. 



17. Parameciens, with a mouth but no prominent row of cilia. 



18. Bursariens, with a mouth and a prominent row of cilia. 



B. — Either voluntarily attached or fixed by the medium of organs. 

 Fam. 19. Urceolariens, voluntarily attached. 



20. VorticeUiens, attached at least temporarily either by their organs or by some 

 part of their body. 



Symmetrical Infusoria. — Of several types without mutual relations. 

 Planariola. Coleps. Chsetonotus. Ichthydium. 



With the exception of the family Leucophry ens, which is nearly equivalent 

 to our subgroup Opalincea, and of the genera Planariola, (Jlu:^tonotus, and 

 Ichthydium (the two last constitute our family Ichthydina), all the other 

 families and genera are members of our class of Ciliata, and are described in 

 the Systematic portion of this work. 



Prof. Siebold (Amitomie der WirbeUosen Thiere) agreed with Dujardin in 

 rejecting the Polygastrica of Ehrenberg as a class, and at the same time em- 

 ployed the term Infusoria, applied after Ehrenberg's example to a multitude 

 of various organisms both animal and vegetable, to designate a comparatively 

 limited group. To this restricted use of the teim we have abeady objected 

 (p. 199) ; we will now, therefore, proceed with the classification in question. 

 Siebold's Infusoria included all those microscopic organisms, exclusive of the 

 Rhizopoda, of supposed animal nature, whether possessing a mouth or not. 

 Of these he made two classes : one named Astoma, the other Stomatoda, the 

 latter equivalent to our Ciliata. The following tabular outUne is presented 



