FLOSCULARIADiE. IT 



on the dorsal surface. A partial separation (probably due to a sphincter muscle) is 

 usually visible between the stomach and intestine, and the distinction is often made 

 more obvious by the different colour of the contained food. The whole alimentarj 

 tract is richly ciliated ; and so is the tube (J) that hangs down into the crop. The cilia 

 can he easily seen in the intestine, when it is partially empty ; and on the tube, when it is 

 everted by the Floscule's disgorging its crop. 



Secreting System. — In the great majority of Eotifera there are two gastric glands, 

 seated on the top of the stomach. I have, however, never been able to detect them in any 

 Floscule, neither has anyone recorded their existence except Ehrenberg and Grenadier. 

 The latter describes and figures them of unusual length in F. campanulata, ] but it is 

 probable that in this matter he is mistaken. He also describes two club-shaped gland 

 in the foot. 



Vascular System.— It is very difficult to trace this in most of the Floscules, owing to 

 the optical difficulties due to their skins. But in 1864 Dr. Moxon [loo. cit.) published 

 a complete account of it in F. campanulata. His figure of the contractile vesicle 

 (PI. II. fig. 3, cv), tlie lateral canals [lc), and of four of the vibratile tagsir/), is so clear 

 as to render any verbal description unnecessary. A fifth vibratile tag was discovered 

 by- Grenadier in F. campanulata [loc. at.), in the side of the coronal cup, near the 

 spot where Dr. Moxon [loc. cit.) had anticipated that it would, some day, be found. 

 Parts of this system have been seen in several other species, and doubtless it exists 

 in all. 2 



The muscles consist of non-striated fibres. Below the bottom of each depression, 

 between the lobes, a muscle runs downwards in the substance of the coronal cup and 

 vestibule, and is lost on the surface of the body, to reappear again, as it nears and passes 

 down the foot. The anterior portions of these muscles end in two or more branches 

 which diverge to the thickened rim of the coronal cup, and often interlace, as seen in 

 F. coronetta (PI. II. fig. 2), and in F. trilobata (PI. II. fig. G), where they may be 

 seen reaching the summit of the dorsal lobe. There are some half-dozen transverse 

 muscles imbedded in the integument of the trunk ; and the walls of the vestibule, with its 

 upper ciliated rim, are all highly contractile. 



The Nervous System. — Dr. Moxon {loc. cit.) has described and figured the nervous 

 ganglion in F. campanulata, and I have seen it in F. IlooJii. It is in nearly the same 

 position as it is in Stephanoceros, namely, on the dorsal side of the vestibule ; and is. as 

 usual, close to the organ of taste, and not far from the eyes and dorsal antenna ; to all 

 of which doubtless it sends out nervous threads. Dr. Moxon has seen and figured such 

 threads in F. campanulata (PL II. fig. 3, v.) 



In the great majority of the Eotifera the mastax is also not far from the nervous 

 ganglion ; but in the Flosculariadce the mastax almost vanishes, wdiile the jaws and 

 ganglion are far apart. 



Organs of Sense. — Two red eye-spots lie usually above the ganglion ; but, as in the 

 adults they are deeply imbedded in the integument, they are not easily seen. In fact the 

 ordinary way of attempting to see them, by transmitted light, will scarcely ever be 

 successful; but by treating the Rotiferon as an opaque object, and concentrating a 

 strong light on it, the eyes may often be seen glowing like rubies when all else is 

 invisible. 3 The eyes are conspicuous in the half-grown animals, and in the young within 



1 Sieb. u. Kail. Zcits. Bel. xix. 1809, p. 483. 



1 Dr. Leyilig saw the contractile vesicle in F. cornula ; Ueb. d. Bait d. Raderth. 185 I. Dr. Bart sch 

 has seen the contractile vesicle, lateral canals, ami vibratile tags in his F. longilobata (F. coronetta) 

 Rot. Hungarice, 1877. 



3 Mr. Gosse (Popular Sci. Rev. vol. i. 18C2, p. ICO) observed one eye at a time in F. cornnta. Mr. 

 Cubitt (Afore. Micr. J. vol. iii. IsTO, p. 2-45) saw tin- eyes in F. coronetta ; and I have recorded (./. Roy. 

 MU r. Soc. i Ser. vol. iii. ls,s;;, p. 163) my having observed them in F. HooJii and F. regalis. Herr 

 K. Eckstein (Sieb. a. KM. Zeits. BcL xxxix. 1883, p. 347), unaware ot the above observations, says 

 " the Floscules have been hitherto regarded as eyeless," and records his having seen the eyes in F. 

 cornula. 



