614 DESCRIPTION OF [Rotatoria. 



These genera are undescribed by Dujardin, Cyphonautes he con- 

 siders a doubtful member of the Rotatoria, and ipould transfer 

 Microcodon to another family, its caudal process being rather an 

 articulated flexible tail than a contractile pedicle. Only Meyalo- 

 trocha is admitted by Siebold. 



Genus Cyphonautes. The hump-hacked Animalcules are desti- 

 tute of eyes. Locomotion is performed by the continuous but 

 notched cilia wreath and internal band-like muscles. The nutritive 

 apparatus consists of a toothless oesophagus, an alimentary canal, 

 with probably a pancreatic gland ; an ovarium, with a single 

 large ovum is visible ; vessels and tremulous gills unknown ; a 

 nervous sj'stem is indicated by a round glandular knot at the 

 oesophagus. 



G. compressus. — Body , white, compressed, obtusely triangular, 

 truncated anteriorly, and sub-acutely gibbous upon the back ; near 

 the oesophageal head is a spherical gland, probably a brain ; no eye 

 with coloured pigment is present ; on each side a band-like muscle 

 proceeds to the end of the back, which terminates in a changeable 

 tuberosity (perhaps suction disc). It swims with a vacillating 

 motion. Fig. 373, P. 8, represents a full-grown animalcule. Found 

 in sea water. Size 1-lOOth. 



Genus Microcodon. The hell little fish Animalcules. — Eye 

 single ; wreath of cilia simple, bent in the middle, so as to resemble 

 the figure 8 lying transversely ; alimentary canal thick and straight, 

 without a stomach ; no oesophageal tube, but a sort of oesophageal 

 bulb and a couple of single-toothed jaws ; also a turbid ovarium. 

 Immediately behind the rotatory apparatus is a small red visual 

 organ, and at the frontal region beside it is a reddish knot whose 

 function is unknown. 



M. cZa?;M5. — Body campanulate, pedicled, the styliform foot-like 

 tail as long as the body ; in the middle of the brow are two bundles 

 of stiff bristles, two pincer-like points, evidently teeth, project out 

 of the middle of the rotatory organ, and are in connection with 

 the reddish jaws. Fig. 371 is a back, and fig. 372 a left side 

 view. Size 1 -280th. 



Genus Megalotrociia. The parasol or great wheeled Ani- 

 malcules. — Eyes two, sometimes becoming effaced by age : rotatory 



