CILIATE PROTOZOA (INFUSORIA) 



275 



40 (41) Body not elongated; spherical to ovate, slightly flexible; a short 



proboscis at the base of which is the mouth. Pharynx 



with rods Trachdius Schrank. 



Representative species Trachelius ovum Ehrenberg 1838. 



Neck highly flexible. Mouth circular; pharynx' with rods. 

 Nucleus central; contractile vacuoles numerous. Endoplasm 

 at the inner end of the pharynx usually spreads out into four 

 or five broadly diverging ramifications. Length 300 p. Fresh 

 water. 



FIG. 474. Trachelius ovum. X 85. (After Blochmann.) 



41 (40) Body greatly elongated, band-like, very flexible; proboscis long with 



mouth at the base and a row of long cilia along its ventral 



side Dileptus Dujardin. 



Representative species. Dileptus gigas Claparede and Lachmann 1858. 

 Body somewhat compressed, often with a pointed, 

 tail-like prolongation. A prominent shoulder or 

 hump often indicates the position of the mouth. 

 Nucleus moniliform, very long.' Contractile vacuoles 

 numerous in a dorsal row. Trichocysts on the ven- 

 tral surface of the neck. Length 500 to 800 M- Pond 

 water. 



FIG. 475. Dileptus gigas. X no. (After Conn.) 



42 (37) Mouth terminal; body elongated with a long proboscis. Nucleus 



double Lionotopsis Conn. 



Representative species Lionotopsis anser Conn 1905. 



FIG. 476. Lionotopsis anser. X 230. (After Conn.) 



43 (36) Mouth usually closed; pharynx when present, without rods. . . 44 



44 (45) With a broad hyaline border; body flattened; proboscis short, mouth 



on the left side. Trichocysts well developed on the right 



side Loxophyllum Dujardin. 



Representative species Loxophyllum rostratum Cohn 1866. 



Anterior extremity prolonged into a dorsally re- 

 flected, uncinate rostrum. Cilia of anterior region 

 longer. Middle of the dorsal border crenulate, the row 

 of trichocysts extending from this region forward 

 nearly to the tip of the rostrum. Nuclei multiple, 

 central; a number of contractile vesicles posterior. 

 Length igo ft. Recorded by Conn from the fresh 

 waters of Connecticut. 



45 (44) Without a broad hyaline border 46 



46 (47) Body flattened, elongated with an acute proboscis at the base of 



which is the mouth. Nucleus single or double. 



Amphileptus Ehrenberg. 



Representative species Amphileptus gutta Cohn 1866. 



Mouth about one-third the length of the body from the 

 anterior end. Pharynx a short smooth tube. Cilia even all 

 over the body. Nucleus-like corpuscles scattered throughput 

 the cortical region. Contractile vacuole single, posterior. 

 Length 125 /* Reported by Conn from Connecticut. Cohn 

 reports the species from salt water. 



FIG. 478. Amphileptus gutta. X 335. (After Conn.) .J 



FIG. 



477- 



Loxophyllum rostratum. 

 (After Conn.) 



X 200. 



