566 ORDER HOLOTRICHA. 



companions as ectoparasites of the same host being Spirochona gemmipara, Lageno- 

 phrys amptilla, and L. nassa, and the remarkable Acinete type Dendrocometes 

 paradoxus. 



Anoplophrya clavata, Leidy sp. PL. XXVI. FIG. 21. 



Body clavate, about five times as long as broad, obliquely and concavely 

 truncate anteriorly, the front margin often expanded and hatchet-shaped, 

 the posterior region attenuate, rounded, or acuminate ; cuticular surface 

 longitudinally striate ; parenchyma granulate, colourless ; endoplast not 

 observed ; an even row of six or eight spherical contractile vesicles disposed 

 along the longer or dorsal border. Length 1-200" to i-ioo". 



HAB. The visceral cavity of Limibriculus limosns. 



This species, originally described by Professor Leidy as Leucophrys clavata, is 

 apparently referable to the present genus. Multiplication by even transverse fission 

 was frequently observed. The characteristic anterior truncation is not conspicuous 

 in the posteriorly produced zooid until some time subsequent to its separation from 

 the anterior moiety. 



Anoplophrya cochleariformis, Leidy sp. PL. XXVI. FIG. 25. 



Body elongate, curved, somewhat variable in form ; the anterior half or 

 third ovate and inflated, the posterior portion narrow and subcylindrical, 

 gradually tapering to its extremity, but sometimes exhibiting a secondary 

 smaller terminal inflation ; contractile vesicles six or seven in number, 

 forming a row along the margin of the narrower posterior region ; endoplast 

 broadly ovate, filling the larger portion of the inflated anterior segment. 

 Length 1-175" to 1-130". 



HAB. Intestinal cavity of Lumbriculus tennis. 



This species was originally described by Professor Leidy * under the name of 

 Lwicophrys cochleariformis. The contractile vesicles and endoplast, although not 

 mentioned in his brief description, are clearly indicated in his accompanying 

 drawings. 



Anoplophrya (P) socialis, Leidy sp. 



Body highly contractile and variable in form, ovate, cordate, fusiform, or 

 globular ; cuticular surface longitudinally striate, entirely ciliate ; enclosing 

 numerous internal vacuoles. Length 1-75" to i-ioo". 



HAB. Intestinal tract of the American fresh-water Polyzoon, Urnatella 

 gracilis, Leidy. 



This animalcule, likewise briefly described by Professor Leidy as a species of 

 Leucophrys, apparently belongs to the present generic group. 



Anoplophrya vermicularis, Leidy sp. 



Body subcylindrical, eight or ten times as long as broad, slightly taper- 

 ing or subacute posteriorly ; the anterior end rounded and flattened ; cuti- 

 cular surface striate longitudinally, shortly and finely ciliate ; parenchyma 

 white, finely granular; contractile vesicles numerous, twenty to thirty in 



* ' Journal Academy Natural Science Philadelphia,' ser. ii. vol. iii., 1855. 



