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Transactions of the Society. 
is ventral whilst the so-called dorsal antenna should in reality be 
known as the ventral antenna, the fact of its being unpaired not 
absolutely militating against this proposition, since we have in 
Conochilus unicornis (a recently discovered species *), the two 
ventral antennae in process of fusion. 
The general anatomy of this rotifer resembles that of T. sejua- 
torialis. The secondary wreath is small, and fringes the oral s.de 
of the buccal orifice. The buccal funnel, which has a pair of large 
leaf-like salivary glands, leads into a powerful mastax. The trophi 
appear to be of a rudimentary malleo-ramate type, but though I 
observed them, I am sorry that I made no sketch, an omission I hope 
to rectify on a future occasion. A long slender oesophagus leads into 
a capacious stomach, with gastric glands on either side. This is 
followed by a large intestine ending in the cloaca. The cloacal orifice 
appears as a transverse slit at the lower part of the dorsal surface. 
As regards the nervous system , a large ganglion situated just 
above the buccal orifice sends nerve-threads to the ventral antenna, 
the two lateral antennae, the two eyes, and the buccal funnel. The 
nerve to the ventral antenna passes straight across the body- cavity, 
on a level with the ciliary wreath,! to the centre of the ventral gap, 
where it turns down and ends in the ventral antenna about the 
centre point of the middle line of the ventral surface. The nerves to 
the lateral antennse pass toward the ciliary zone, and on a level with 
it, and then suddenly turn downwards to end in the lateral antennae at 
the junction of the lower fourth with the upper three-fourths of the 
body. The lateral antennae are in close connection with the vascular 
system. The two eyes are situated on the ciliary wreaths, a little 
to the dorsal side of a meridian line bisecting the sphere. Each con- 
sists of a beautiful crimson hemisphere surmounted by a clear hyaline 
lens (fig. 2 c). 
The main mass of the Vascular System is suspended on either side 
of the body-cavity, just below the eyes and the ciliary zone (fig. 2, c). 
The lateral canals are entirely separate from what is evidently 
analogous to the granular floccose material which generally surrounds 
them, but which in this case is differentiated into a separate organ, 
which I regard as the “ nephridiuyn,” consisting of an intricate net- 
work of winding and intercommunicating canals, lying close under 
the cutis, and lined with cells having large yellow nuclei. The 
nephridium communicates below with the lateral antenna, and both 
above and below with the lateral canal. To the limited portion of 
the lateral canal between these junctions are attached the vibratile 
tays, five in number, each vibratile tag consisting of a cylinder 
crowned with a conical cap, and containing a long flagellum. The 
main canal passes towards the dorsal surface, sending an off-shoot 
* Jonrn. Quek. Micr. Club (1892) ser. ii. vol iv. p. 867. 
t In T. sequatorialis , Dr. Semper describes this nerve as passing clo«e beneath the 
cutis of the aboral hemisphere. Mon. Micr. Journ., xiv. (1875) p. 288. 
