CILIATE PROTOZOA (INFUSORIA) 



273 





21 (18) With a terminal bristle. Similar to Holophrya in shape. 



Urolricha Claparede and Lachmann. 

 Representative species. 



Urotricha farcta Claparede and Lachmann 1858. 



Body obliquely striated; posterior bristle obliquely directed 

 when at rest. Progression by slow forward movement or sud- 

 den leaps to one side. Mouth on a small circular prominence 

 at the anterior end. Length 20 /* Pond water. Balantozoon 

 of Stokes agrees with this genus except that only the anterior 

 two-thirds is ciliated. 



FIG. 465. Urolricha farcta. X 435. (After Conn.) 



22 (17) Anterior end oblique .. 23 



23 (24) With a spiral series of long cilia on either side of a ridge extending 



from the anterior border to the posterior extremity. 



Perispira Stein. 



Representative species Perispira strephosoma Stokes 1886. 



Body elongate-ovate. Cilia of the general surface very fine. 

 Protoplasm filled with dark-colored corpuscles. Length 80 /*. 

 Standing water with sphagnum. 



FIG. 466. Perispira strephosoma. X 280. (After Stokes.) 



24(23) Without a spiral series of cilia ..... .-. . . . 25 



25 (26) Elongated, with mouth slightly on one side; uniform ciliation. Nu- 



cleus single. Enchelys Hill. 



Representative species Enchelys pupa Ehrenberg 1836. 



Body inflated, slender anteriorly. Often colored green. 

 Length about 200 /* Stagnant water. 



FIG. 467. Enchelys pupa. X 150. (After Conn.) 



33PP*^ 



26 (25) Elongate, sac-like, mouth occupying the oblique surface. Pharynx 



slightly developed, sometimes with rods. Nucleus bead- 

 like Spathidium Dujardin. 



Representative species. . . . Spathidium spathula Dujardin 1841. 



mij'tfjuuarttitott,,,,,.,.,,, **- Very difficult to distinguish from forms of the genus 



FIG. 468. Spathidium spathula. X 250. (After Conn.) 



27 (16) With pharynx well developed 28 



28 (33) Body greatly elongated 29 



29(32) Body flattened. V. 30 



30 (31) Flask-shaped with an elongated neck-like anterior end. Proboscis 

 short, retractile. Mouth terminal leading into a long 

 pharynx. ... Trachelophyllum Claparede and Lachmann. 

 Representative species. . Trachelophyllum tachyblastum Stokes 1884. 

 Body eight or ten times as long as broad; neck slender; 

 pharyngeal passage indistinct, narrow, longitudinally stri- 

 ate. Cilia of surface long, vibrating independently. 

 Nuclei two, subcentral. Contractile vacuole posterior. 

 Length, extended, 120 to 150 p. Bottom of shallow pools. 



FIG. 469. Trachelophyllum tachyblastum. cv, contractile vacuole; 

 macn, macronudeus. X 250. (After Stokes.) 



