Ciliophora 393 



Kent (Fig. 7. 35, C); (9) Ptychocyclidae: Plychocyclis Brandt; (10) Rhabdonellidae: 

 Epirhabdonella K. & C, Protorhnbdonella J., Rhabdonella B., Rhabdonellopsis K. & 

 C; (11) Tintinnidae: AlbatrossicUa K. &: C, Amphorella Daday, AmphorcUopsis K. 

 & C, Brandt iella K. & C, Bursaopsis K. & C, Canthariella K. & C, Dadayiella K. & C, 

 Daturella K. & C, Epicranella K. & C, Epirhabdosella Campbell, Eutintinnus K. & C. 

 (Fig. 7. 35, J), Odontophorella K. & C, Ormosella K. & C, Proamphorella K. & C, Pro- 

 stelidiella K. & C, Rhabdosella K. & C, SaJpingacantha K. fe C. Salpiiigella J. (Fig. 7. 

 35, D), SalpingcUoides Campbell, Stelidiella K. & C, Steenstrupiella K. & C, Tintinnns 

 Schrank; (12) Undellidae: Amplcctella K. & C. AmplecteUopsis K. & C, CricundeJla 

 K. & C, Proplectella K. & C, Undella Daday, Undellopsis K. & C; (13) Xystonellidae: 

 Parafavella K. & C, Parundella J., Xystonella Brandt, Xystonellopsis J. 



Suborder 4. Entodiniojnorphina 



These ciliates occur in the rumen of cattle, sheep and other ruminants 

 and in the intestine of certain other herbivores. The ciliature is much 

 reduced and in the simplest Ophryoscolecidae, as represented by Ento- 

 dinium (Fig, 7. 36, P), is limited to the membranelles of the adoral zone. 

 In most Ophryoscolecidae, however, there is also a dorsal zone of mem- 

 branelles, ranging from a short anterior band to a longer and more or 

 less equatorial row (Fig. 7. 36, A-E). The adoral membranelles arise in a 

 furrow formed by an ectoplasmic fold and extend spirally to the cytostome 

 which lies in an elevated oral disc at the anterior pole. At least the adoral 

 zone, and in some genera the dorsal zone also, can be retracted. Between 

 the adoral and dorsal zones there is often an elevation, the operculum 

 (Fig. 7. 36, M, R). The Cycloposthiidae have added one or more posterior 

 or caudal rows or tufts of membranelles (Fig. 7. 38, A). 



Beneath the firm pellicle there is a distinct cortical layer (Fig. 7. 36, 

 P) with a clear matrix containing many granules. The macronucleus, 

 micronucleus, contractile vacuoles (143), and skeletal plates also lie in 

 this zone, which is separated from the endoplasm by a membrane con- 

 tinuous anteriorly with the pharynx and posteriorly with the rectum. 

 The cytostome (Fig. 7. 38, B) opens into the short pharynx (Fig. 7. 36, 

 R). The endoplasmic sac, consisting of the bovuidary membrane and the 

 contained endoplasm, fills most of the body posterior to the pharynx. The 

 rectum, at the posterior end of the sac, is a thin-walled tube extending 

 through the ectoplasm to the anus. In certain Ophryoscolecidae, the wall 

 of the rectum apparently contains myonemes which presumably have a 

 sphincter-like action. 



Skeletal plates are present except in a few of the Ophryoscolecidae 

 (Diplodinhim, Entodinium, Eodinium). These structures vary in nimiber, 

 size, form, and arrangement in different genera (Fig. 7. 36, F-L). Each 

 plate is a flattened structure extending posteriorly in the ectoplasm from 

 a level shortly behind the adoral zone (Fig. 7. 36, Q). The plates of 

 Polyplnstron multivesiculatum consist of a protein matrix containing ir- 

 regular platelets of "paraglycogen" (144). 



The Entodiniomorphina are divided into two families: tiie Ophryo- 



