INFUSORIA. 



[ 421 ] 



INFUSORIA, 



acid. The juice of the common horse-shoe 

 geranium is a very old agent for elFecting 

 the same purpose (Kent). The various 

 colouring- matters — eosine, haematoxyhue, 

 aniUne, picrocarmine, kc. — serve to distin- 

 guish the nuclei &c. 



The chemical properties of the sarcode 

 or protoplasm of the lower animals and 

 plants, are very important to be noted. For 

 although proteine matter exists in both, 

 yet in the vegetable forms this is in very 

 small proportion, and tlie motile power is 

 correspondingly feeble. Solution of potash or 

 ammonia dissolves the proteine matter, and 

 as the animal organisms are almost entirely 

 compos.'d of this, their bodies vanish; while 

 in the case of vegetable organisms, the pre- 

 ponderating cellulose matters remain, the 

 organism apparently undergoing no change. 

 Probably if this test were applied to the 

 Flagellate forms, few would be left among 

 the Infusoria ; and it should be used in all 

 cases. 



The systematic arrangement of the Infu- 

 soria is in an unsettled state. The charac- 

 ters of the genera and species laid down by 

 Ehrenberg were mostly founded upon analo- 

 gies rather than upon observation. Those 

 proposed by Dujardin were far more accor- 



dant with observation ; but unfortunately 

 this author so altered the names proposed 

 by Ehrenberg, raking up old and long-for- 

 gotten names, which are moreover often 

 doubtfully identical with those for which 

 they are substituted, and sometimes using 

 similar names for totally different genera 

 and species — that great confusion was pro- 

 duced, and the two systems are not recon- 

 cilable. 



The later system of Claparede and Lach- 

 mann was a great improvement upon the 

 former ones ; and this has been strengthened 

 and improved by those of Stein and Kent. 

 The standard work of the latter is replete 

 with laborious research ; and contains de- 

 scriptions and figures of all the species. 



In descriptions of genera and species the 

 anterior part of the body is that near which 

 the eye-specks are situated, and which is di- 

 rected forwards ; the surface towards which 

 the eye-specks are nearest forms the back 

 or dorsal surface. A narrowing of the body 

 posteriorly, so as to give rise to a prolonga- 

 tion, forms a tail ; and an anterior prolon- 

 gation of the dorsal surface is described as 

 a forehead or upper lip, according to its 

 situation. 



According to the system of Claparede and Lachmann, the Infusoria are arranged as follows : — 



I. CiLIATA. 



SucroRiA. 



rx a 11 < Cilia also present '. Order III. Cilio-plaGELLATA, 



One or more fiagella ^ j^^ ^j^^ i Order IV. Flagellata. 



■NT^ florroiiMvn / Cilia or brlstlcs 111 the adult ; no suckers Order 



nonageiium 1 Ho cilia in the adult ; suckers present Order II 



Mouth and oeso- 

 phagus open in 

 repose, the latter 

 ciliated, neither 

 dilatable 



Mouth and oeso- 

 phagus very dila- 

 table ; oesopha- ' 

 gus not ciliated . 



Order I. Ciliata. 



'Mouth and anus in a common fossa. Buccal spiral deiiotrope 1. 



( Buccal cilia f ^? °''^'','' locomotive organs than the 



2v 1 buccal oilia 2. 



•' L Crawling locomotion 3. 



Buccal spiral laeo-"] /Body bell-shaped, several rows of 



I I buccal cilia 4. 



( Cilia all over ■< Buccal spiral f Buccal cilia strong- 

 forming one-! est 5. 



I turn only ... (.No buccal spiral 6. 



C rAfoot 7. 



I Body entirely or mostly ciliated •••■{ ]Vo f^^t j ^'o carapace 8. 



I [ ■" (A carapace ; 9. 



^Body glabrous, one row of cilia around the mouth 10. 



Mouth and anus not i 

 in a common fossa. J 



trope 



Fam. VorticelUna. 



Fam. TJrocentrina. 

 Fam. Oxytrichina. 



Fam. Tintinnodea. 



Fam. Sursarina. 

 Fam. Colpodea. 

 Fam. Di/sterma, 

 Fam. Trachelina, 

 Fam. Colepina. 

 Fam. Halterina. 



Order II. Suctoria, or Acinetina. 



Not forming a 

 branched colony. 



/A peduncle 1. Genna Podophrya. 



No sheath... •< Tvr j i fFree 2. Genua Sphcerophrua. 



\ ^o peduncle { ^-^^^ _ 3 ^^^^^ Trichopkria. 



fSuckers simple ... J orancnea coiony. i jApeduncle 4. Genus ^a«./a. 



ij-sneatn ••• -[jfo peduncle b. Gunm Solenophrya. 



V Forming branched colonies 6. Genus Dendrosoma. 



!,Sucker8 branched 7. Genus Dendrocotnefet. 



Suckers on a long retractile tube 8. Genus Ophryodendron. 



#ucker8 not on a ^ 

 proboscis or tube." 



