400 BIOLOGY OF THE PROTOZOA 



The following genera have only one primary tentacle : 



1. Rhynchophrya, with stalk and with 1 or 2 secondary tentacles. 



2. Rhyncheta, no stalk, attachment by protoplasmic body, 1 

 tentacle (?). 



The following genera have many tentacles: 



3. Thaumatophrya, tentacles conical with enlarged bases. 



4. Discophrya, except for coriacious membrane similar to Acineta. 



5. Choanophrya, tentacle expansile at extremities for food taking. 

 Family 4. Dendrosomidae.— The individuals included in this 



family are highly variable in form frequently with a creeping proto- 

 plasmic stolon and with a well marked tendenc}^ to branch; stalks 

 are exceptional. Tentacles are of one type only (suctorial). Fre- 

 quently ectoparasitic. 



1. Rhabdophrya, body not branched, cigar- or rod-shape; with 

 stalk. 



The following genera are not stalked but the body is attached : 



2. Trichophrya (Fig. 91, p. 185), ectoparasitic, tentacles in 

 fascicles, no branches. 



3. Dendrosoma (Fig. 159, p. 308), with basal stolon, erect branches 

 bearing tentacles. 



4. Lcrnceophrya, base with short unbranched processes bearing 

 fascicled tentacles. 



The following genera have no stalks and are unattached : 



5. Tetroedrophrya, body tetrahedral in form. 



6. Stmirophrya, body with 6 processes of like character. 



7. Astrophrya, body with 8 radiating processes each with a 

 fascicle of tentacles. 



Family 5, Dendrocometidse.— These are forms with somewhat 

 specialized processes termed "arms" which may or may not be 

 branched. They are attached forms with tentacles of one kind only. 



1. Dendrocometes, with branched arms, each branch with one 

 sucker. 



2. Stylocomctcs; with simple, unbranched arms. 



Family 6, Ophryodendridse. — In this family, with only one genus— 

 Ophryodendron—an arm-like process is still further differentiated 

 to form a retractile proboscis which bears the suctorial tentacles. 

 Little is known of the life history. 



Family 7. Ephelotidae.— The only forms of Suctoria with two 

 types of tentacles— suctorial and prehensile or piercing— are included 

 in this family. They are naked or cup-bearing and are with or with- 

 out stalks. Reproduction is by external budding. Usually para- 

 sitic on marine animals particularly hydroids. Sexual processes 

 are unknown. 



1. Ephelota (Fig. 11 1, p. 230), without test or cup, with or without 

 stalks ; usually on hydroids. 



2. Podocyatlms, with test and stalk. 



