702 SYSTEMATIC HISTORY OF THE INFrSOEIA. 



elongated toes, foiu' little homs or processes, and six points. Muscles for 

 moving the foot are also visible. The oesophageal bulb has two jaws, with 

 numerous delicate teeth. The filiform alimentary canal has a bladder-Hke 

 expansion posteriorly, but is not provided with glands : it is siuTounded by a 

 granular and cellular mass, whose function is unknown ; Ehi-enberg thinks 

 it connected with reproduction. An ovarium, with single large ova, is seen. 

 A little spur-like process projects from the neck. No indication of a nervous 

 system is observable. 



Callidina elegans. — Spindle-shaped, | in the cesophagus. Swims in rather an 



crystalline ; rotary organs, or wheels, 

 small, (xxxiv. 470-472 ; 473, the eggs.) 

 In bog- water and infusions of oak-bark. 

 1-72". 



C. rediviva (Ehr.). — Fusiform, dif- 

 fusely granidar or else fleshy ; with red, 



eel-like manner. C. constricta (Duj.), so 

 named on accoimt of the contracted fonu 

 of its rotary apparatus. Its jaws pre- 

 sent a row of closely-set parallel teeth. 

 1-52". ^ ^ 



C. hklens (Gosse). — Body spindle- 



distinct ova, and strong rotary organs. I shaped, jaws fmiiished with two distinct 

 1-60" to 1-48"; ova 1-576". Berlin; in ! teeth. 1-45". Perhaps this is no other 

 the sediment of water-spouts of houses, than C. elegans, the jaws of which Ehr- 

 C. co?'nuta. — On each side of the head i enberg describes as having many delicate 



a short horn-like process. Maxillary 

 bulb much wider behind than in C. ele- 

 gans. Ciliary motion unusually strong 



teeth. I have, however, examined nu- 

 merous specimens, and have always foimd 

 them distinctly two-toothed. 



Genus HYDRIAS (XXXY. 474).— It is devoid of eyes, proboscis, and the 

 little horn-like processes at the foot ; the two small rotary organs, or wheels, 

 are supported on pedicles or arms. 



An oesophageal head, and an ovary, with a large ovum, have been seen by 

 Ehrenberg. The form is like a naked Pterodina. This genus is constructed 

 for an Afi-ican Eotatorian imperfectly observed. 



Hydrias cornigera. — Ovate, hyaline ; 

 foot attenuated, resembling a tm-cate 

 tail. XXXV. 474 represents an animal- 

 cule extended. With Oscillatoriae, in 



standing water from a small spring at 

 Siva, in the Oasis of Jupiter Amnion. 

 1-190". 



Genus TYPHLIXA (XXXY. 475).— Like the last, is an African forai. 

 Devoid of eyes, proboscis, and horn-Kke processes at the base of the foot ; 

 but its little wheels are sessile. It resembles a very small Botifer, without 

 frontal probpscis or eyes. 



Typhlixa viridis. — Body oblongo- | near Cairo in Eg}^t, in such numbers as 

 conical, small (xxxv. 475). Foimd by | to colour the water gTeen. 1-720". 

 Drs. Hemprich and Ehrenberg in a pool I 



Genus ROTIFER (XXXY. 476-480 ; XXXYIII. 1-3).— Body fusiform. 

 Able to retract and protrude its little foot with its appended horns. Eyes 

 two, placed upon the frontal proboscis ; foot provided with little horn-like 

 (cornicidate) processes, and two toes bisulcate at theii* apices. A double 

 rotary organ, fiu'nished with muscles, is seen in all the species ; also longi- 

 tudinal and foot muscles in three of them ; a furcate foot and hom-like pro- 

 cesses in four species ; in R. citrinus the pincer-like portions of the foot 

 appear to be tri-pointed ; in R. erythrwus they seemed to be drawn in. 

 In four species a muscular oesophageal bulb, with jaws, each two-toothed, is 

 seen ; in three species the alimentaiy canal is filiform, ^vith a vesicular 

 expansion at the extremity, but no oesophageal tube ; it is moreover sur- 

 rounded by a cellular glandulose turbid mass ; another species has a conical, 

 tubular ahraentary canal, without the surroimding mass or expansion at the 



