Ciliophora 383 



tudinal rows. The peristome is a pouch with a triangular opening, 

 through which the short adoral band of membranelles is not easily 

 recognizable from the outside (214). Numerous long fibrils extend into 

 the endoplasm from the basal granules of cilia and membranelles. 



Family 2. Bursariidae. The most characteristic feature is a large funnel- 

 shaped peristome, closed ventrally throughout part or most of its length 

 (Fig. 7. 29, F-I). This ventral closure is perhaps the result of overgrowth 

 of the "oral lip," a plate-like extension of the body wall which extends 

 mediad from the right margin of the peristome in various Heterotrichina. 

 In the Bursariidae this extension presimnably has fused with the right 

 margin of the peristome. The undulating membrane has disappeared in 

 most species. 



Three genera are referred to the family: Bursaria Miiller (134; Fig. 7. 29, F-I), 

 Bursaridium Lauterborn (104; Fig. 7. 29, J), and Thylacidium Schewiakoff (104). 



Family 3. Chattonidiidae. These ciliates show a superficial resemblance 

 to the Oligotrichina in that the peristome is shifted to the anterior pole. 

 The membranelles form an almost complete spiral around the margin of 

 the peristomial funnel, at the base of which lies the cytostome (Fig. 7. 

 29, K). Within the ring of membranelles, an undulating membrane ex- 

 tends for some distance around the peristome. The somatic ciliation is 

 uniform. 



The genus Chattonidium Villeneuve (214; Fig. 7. 29, K, L) is the only one assigned to 

 the family. 



Family 4. Clevelandellidae. These are completely ciliated heterotrichs 

 which taper toward the anterior (aboral) pole. A zone of membranelles 

 extends into the funnel-shaped peristome to the pharynx (Fig. 7. 30, 



G, N). 



The family includes two genera, both represented by species in the digestive tract 

 of wood roaches (Panesthia): Clevelandella Kidder (112; Fig. 7. 30, E, F, N) and 

 Paradevelandia Kidder (112; Fig. 7. 30, G). 



Family 5. Condylostomidae. The large broad peristome is bordered on 

 the left by the adoral zone of membranelles (Fig. 7. 30, D). On the right, 

 a long undulating membrane arises from a groove hidden by a ventral 

 ledge ("oral lip"). This ledge is extended to the left in several species to 

 form a floor for part of the peristomial cavity. On the antero-ventral 

 surface, there is sometimes a progressive replacement of simple cilia by 

 fused groups of cilia, culminating in a zone of cirri at the right margin of 

 the peristome (Fig. 7. 30, C). 



