10 THE ROTIFERA. 
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. le). 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. 1a), in which a thin line of green food 
marks the hollow of the nearly empty stomach. The secreting and vascular systems 
are obyious and normal. A rectangular nervous ganglion (fig. 1) below the corona, 
and just under the dorsal surface, sends off a pair of nervye-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 antenne (fig. la, 1b), and the other two nerve-threads pass to 
the dorsal antenna (fig. 1b). 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 Hnteroplea 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 sufficiently shown in fig. 17. 
Disease.—I once found a few specimens of H. senta (fig. 1m) 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, suffers from an internal parasite. It is of a narrow oval form, 
about +4, 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,1/). There are curious 
bodies inside the parasite itself something like the globe of a lamp in shape (fig. 1). 
Length. From ;'; inch to 3 inch. Habitat. In water swarming with Huglene, 
&e.: common, 

Genus RHINOPS, Hudson. 
GEN. CH. Body conical, tapering to the foot ; along dorsal proboscis on the corona ; 
foot short, and confluent with the trunk, with two minute toes clesely pressed together ; 
eyes two, at the end of the proboscis. 
R. vitreA, Hudson. 
(Pl. XIV. fig. 2.) 
Rhinops vitrea.. : c C Hudson, Ann. Nat. Hist. 4 Ser. vol. iii. 1869, p. 27, pl. ii. 
Plate, Jenaisch. Zeits. f. Natur. Bd. xix. 1885, p. 46. 
” ” . . . . 
Rhinops vitrea appears to have escaped notice till 1869, 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 Adineta. 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 
