112 THE VICTORIAN NATURALIST. 



nervous and vascular systems, eyes deeply buried in the 

 integument, and a minute antenna on the dorsal lobe. This 

 favourite and beautiful genus is represented in our pond by 

 several species. We believe we have been able to identify 

 F. cornuta, F. coronetta, F. omala, and a large species without 

 knobs is probably F. campanulata. The drawing represents F. 

 cornuta, which, when favourably seen, is recognizable by the 

 long, finger-like, flexible process attached to the dorsal lobe of 

 the corona. The Floscules, which often present brilliant colora- 

 tion — green and brown — in the stomach and intestine, are 

 partially enclosed in a wide sack-like tube. This, from the 

 extreme tenuity of the material, is frequently almost invisible. 

 Six or more eggs may sometimes be seen in the tube, ranged 

 along the animal's slender foot. Some Floscules have the vice of 

 gluttony. They have been seen to overload their crops so 

 greatly that a complete block ensued. In this extremity the 

 animal turns its front part literally inside out, expels the contents, 

 and, resuming its normal form, commences again — like a good 

 old Roman epicure. 



During our study of this, the more stable part of the Rotifer 

 population, other and very different species have appeared — 

 creeping like leeches, or swimming among the weeds. Lithe and 

 flexible, these can bend their bodies double, elongate them 

 enormously, or roll them up into compact little balls. These all 

 belong to the second order of Rotifera — the Bdelloida (Gr. 

 bdella, a leech), and to the family Philodinadse. One description 

 virtually applies to all. In addition to the peculiarities just 

 mentioned, they possess a corona consisting of two circular lobes 

 set side by side and surrounded by a double wreath of cilia. 

 The principal wreath, in motion, presents strikingly the appear- 

 ance of a pair of rotating wheels. These, however, are not fully 

 complete. An arc is, as it were, cut out of each, towards the 

 centre of the corona. The Philodinadse possess also a character- 

 istic foot. It is telescopic — that is, it consists of several joints, 

 so graduated in size that each can be drawn into the one above, 

 as in a ship's telescope. The last joint has three toes, and the 

 second last a pair of spurs. The animal, at rest, draws these 

 down, holding on by them as well as by the toes. The telescopic 

 idea is carried still further in this family — a three-jointed dorsal an- 

 tenna being constructed on the same plan. The Philodinadse 

 have a tendency towards yellow colour, and often present a 

 fluted or corrugated appearance of the skin, running lengthwise, 

 strongly marked in some specimens. Attention must be paid to 

 the frontal column — a short, thick projection which appears at the 

 front of the head in species of this family before the corona is 

 unfurled. By the aid of this two genera are distinguished. Of 

 the genus Philodina, the large handsome species P. citrina may 



