10 THE itOTIFEIlA. 



also on its whole surface, and may fairly be considered to be the buccal funnel. At its 

 base, close to the ventral surface, lies the mastax, containing malleate reddish trophi 

 with unci of four arrow-like teeth (fig. \e]. I have often seen these hand-like unci pro- 

 truded into the funnel to grasp some desired morsel. The thick cellular walls of the 

 stomach are well seen in the young specimen (fig. la), in which a thin line of green food 

 marks the hollow of the nearly empty stomach. Tlie secreting and vascular systems 

 are obvious and normal. A rectangular nervous ganglion (fig. 1) below the corona, 

 and just under the dorsal surface, sends off a pair of nerve-threads at each corner. The 

 upper pairs possibly ramify to the styligerous prominences which are very sensitive ; 

 and which Mr. Gosse has seen individually depressed below their usual position by mus- 

 cular threads rising up to them from the depth of the head. One of the lower pairs 

 supplies the two lateral antennae (fig. 1((, 16), and the other two nerve-threads pass to 

 the dorsal antenna (fig. lb). The ovary in the half-grown animal (fig. la) is very 

 transparent, and the oviduct is then conspicuous ; as are also the fibres that tie the 

 ovary to the body-walls. 



The male was described by Ehrenberg under the name Enteroplaa hydatina, as 

 he was not aware of its sex. It is often to be met with among the swarms of females 

 that haunt dirty farmyard ponds and neglected water-butts. Its general appearance is 

 that of a young female, but it can be recognised at a glance by the absence of the 

 mastax. Its internal structure is precisely like that of the male of Asplanchna pri- 

 odonta, and is sufliciently shown in fig. In. 



Disease. — I once found a few specimens of H. scnta (fig. 1?») with what appeared to 

 be the mycelium of a fungus growing in the perivisceral fluid, and loosely surrounding 

 the various organs. The infected creatures, however, seemed as vigorous as the healthy 

 ones. H. senta, too, suflers from an internal parasite. It is of a narrow oval form, 

 about -g-J^ inch in length, and swims up and down its host's stomach by jerking the 

 contents of its body constantly backwards and forwards (figs. 1h, Ih). There are curious 

 bodies inside the parasite itself somethmg like the globe of a lamp in shape (fig. IZ). 



Length.. From ^'^ inch to ^^V inch. Habitat. In water swarming with Euglcna, 

 &c. : common. 



Genus BHINOPS, Hudson. 



GEN. CH. Body conical, tapering to the foot ; a long dorsal proboscis on the corona ; 

 foot short, and confluent with the trunk, tvith tivo minute toes clesely pressed together ; 

 eyes two, at the end of the prohoscis. 



B. viTEEA, Hudson. 

 (PI. XIV. fig. 2.) 



Bhinops vitrea .... Hudson, Ann. Nat. Hist. 4 Ser. vol. iii. 1869, p. 27, pi. ii. 

 „ „ .... I'la.te, Jetiaisch. Zeits. /. Natur. Bi. xis-. 1885, i>. iG. 



Bhinops vitrea appears to have escaped notice till 18G9, when I found it in a pond in 

 Losely Park, near Guildford ; so I suppose it must be rare : and yet I have often taken 

 it in the neighbourhood of Clifton, and at times even in abundance. Though not a 

 large Rotiferon, it is easily recognized with a hand-lens by its slow, deliberate way of 

 swimming ; a peculiarity which first attracted my attention to it. Its shape is striking. 

 It is a Hydatina without any styligerous lobes on the corona ; but bearing, in lieu of 

 them, a unique prolongation of the dorsal surface into a sort of proboscis. Two splendid 

 ruby eyes are placed on the extremity of this proboscis, and its under surface is furred 

 with cilia like the prone face of Adincta. The outer ciliary wreath is carried up each 

 side of the proboscis ; but the tip between the eyes is free from cilia, and seems to act 



