Ilydatinaea?^ infusoeial animalcules. 633 



FuECULAEiA coeca (Gossc). — Body cylindrical ; eye wanting, or 

 not discernible ; toes slender, obtuse. Length, including toes, 

 l-135th. Leamington. 



Genus MoNOCEKCA — The filiform-tailed Rotatoria, seated upon a 

 ganglionic mass, eye single, situate in the neck, foot simple, sty- 

 liform, resembling a tail. In two species the vibratile cilia are 

 distributed into about six bundles, their bandlike longitudinal 

 muscles, and those of the foot, producing locomotion ; the sides of 

 the oesophageal head are unequal, as also the two jaws, which have 

 one or two teeth ; the ocsopliagcal tube is curved and long, and the 

 simple alimentary canal conical, with two ear-like pancreatic glands 

 anteriorly. An ovarium and a contractile vesicle are evident. In two 

 species a projecting respiratory tube at the frontal region indicates 

 the existence of the vascular system. 



M. rattus {Trichoda rattus, M.) — Body ovate, oblong, truncated 

 anteriorly, and unarmed ; foot styliform, the length of the body. 

 This creature swims slowly, in a stiff manner ; when stationary, it 

 throws the styliform foot backwards and forwards. The ovarium 

 has a reddish colour ; behind it lies a roundish contractile vesicle. 

 The foot has a short base, with a coi'date internal muscle, and 

 four unequal bristles. Amongst Conferva, t&c. Length 1-1 20th. 



M. bicornis. — Body ovate, oblong, truncated in front, armed with 

 two spines; foot styliform, a little shorter than the body; the 

 oblique oesophageal head exhibits delicate transverse corrugations ; 

 it has a bent and a straight jaw, with probably three teeth in each. 

 Fig. 399 represents an animalcule (right side); fig. 41/ another, 

 contracted, and having its rat-like tail bent. Length l-72nd. 



M. (?) valga {Vorticella vaUja, M.) — Body small, almost cubical, 

 with distinct head, an elevation on the back, and a conical foot, 

 unequally forked ; the rotatory organ, during contraction, shows 

 four muscular sheaths, and the distinct red eye is placed upon 

 a less distinct ganglion ; the oesophageal head is not evident. 

 Length l-288th. 



M. brachyura (Gosse.) — Form that of M. rattus, but the foot 

 short (one fourth of total length), slightly curved, and horizontally 

 flattened ; a large eye in the occiput, and another small one in the 

 breast. Length, including foot, 1- 135th. 



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