chap, vi CILIATA I U 



I. ClLIATA 



Infusoria, with a mouth, and cilia by which they move and 

 feed ; usually with undulating membranes, membranellae, cirrhi, 

 or some of these. Genera about 144 : 27 exclusively marine, 50 

 common to both sea and fresh water, 27 parasitic on or in Meta- 

 zoa, the rest fresh water. Species about 500. 

 We divide the Ciliata thus : l 



(I.) Mouth habitually closed, opening by retraction of its circular or slit- 

 like margin ; cilia uniform . Order 1. Gymnostomaceae. 

 Lacrymaria, Ehrb. ; Loxodes, Ehrb. ; Loxophyllum, Duj. ; Lionotus, 

 YVrez. ; Trachelitis, Schrank ; Amphileptus, Ehrb. ; Actinobolus, St. ; 

 Didinium, St. ; Scaphiodon, St. ; Bysteria, Huxl. ; Coleps, Nitzsch. ; 

 Dileptus, Duj. ; Ileonema, Stokes ; Mesodinium, St. 

 (II.) Mouth permanently open, usually equipped with one or more undu- 

 lating membranes, receiving food by ciliary action (Tricho- 

 stomata, Biitschli) 



(a) Cilia nearly uniform, usually extending over the whole body, 



without any special adoral wreath of long cilia or membra- 

 nellae ; mouth with one or two undulating membranes at its 

 margin or extending into the short pharynx. 



Order 2. Aspirotrichaceae. 

 Paramecium, Hill ; Colpoda, 0. . Mull. ; Colpidium, St. ; Leuco- 

 phrys, Ehrb.; Cyclidium, CI. and L. ; Lembaddon, Perty; 

 Cinetochilum, Perty ; Pleuronema, Duj. ; Ancistrum, Maup. ; 

 Glaucoma, Ehrb. ; TJronema, Duj. ; Lembus, Cohn ; Urocentrum, 

 Nitzsch ; Icthyophtheirius, Fouquet. 



(b) Strong cilia or membranellae forming an adoral wreath, and 



bounding a more or less enclosed area, the " peristome," at 

 one point of which the mouth lies, 

 (i.) Body more or less equally covered with fine cilia ; adoral 

 wreath an open spiral Order 3. Heterotrichaceae 

 Spirostomum, Ehrb. ; Bursaria, 0. F. Mull. ; Stentor, 

 Oken; Fo lliculina, Lamk.; Conchophtheirus, St.; Balan- 

 tidium, CI. and L.; Nyctotherus, Leidy ; Metopus, CI. and 

 L. ; Caenomorpha, Perty ; Discomorpha, Levander ; 

 Blepharisma, Perty. 

 (ii.) Body cilia limited in distribution or absent ; peristome 

 anterior, nearly circular, sinistrorse. 



Order 4. Oligotrichaceae. 

 Halteria, Duj. ; Maryna, Gruber ; Tintinnus, Schrank ; 

 Dictyocystis, Ehrb ; Strombidium, CI. and L. ( = Tor- 

 quatella, Lank.). 

 (iii.) Peristome extending backwards along the ventral face, 

 which alone is provided with motile cirrhi, etc. ; dorsal 

 cilia fine, motionless. . Order 5. Hypotrichaceae. 



1 Orders 1 and 2 constitute together the Holotricha of Stein ; Biitschli regards 

 3 to 6 as sections of Spirotrocka. 



