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Transactions of the Society. 
peculiarities. Its position is upside down, as it were, with the biting 
parts of the trophi directed downwards and inwards ; a long thin- 
walled, chitinous tube connects the mouth opening on the ciliary 
wreath with the lower part of the mastax, and small particles of food 
were seen gliding down this tube to the jaws. This arrangement is 
quite unknown in any other rotifer. The trophi are shown in fig. 3, 
c and d ; they consist of a rod-shaped fulcrum, two rami, and two 
unci ; the outer points of the latter are connected by a very thin 
stirrup-shaped piece ; the manubria are absent. The tube is fixed 
at the point where the rami and unci meet and remains attached to 
the trophi when dissolved out with potash. 
The stomach, which begins at once behind the mastax, is very 
large, saccate, and interspersed with numerous large orange and white 
oil-globules ; it is partly coloured blue and partly green. The blue 
colour resides in the cells of the stomach, but the green appears to be 
due to food particles, and is sometimes absent. A small, conspicuously 
ciliated intestine is situated at the posterior end near the root of the 
foot ; it terminates in a cloaca in the usual way. Dr. Zacharias 
states that there is no anal opening, but this is incorrect, as I have 
observed the discharge of faeces. Gastric glands and lateral canals, if 
present, could not be distinguished owing to the nature of the stomach. 
A rounded ovary and a contractile vesicle, both situated near the 
foot, and four vibratile tags on each side are present. Animals have 
been observed to deposit their eggs on the glass slip, and they do not 
carry the eggs with them ; a prickly winter egg was seen in one 
animal. 
The brain is a large rounded and cellular sac with a neck reaching 
forward to the corona, and white in colour. A large red eye, often 
surrounded by white opaque granules, is situated on the under side of 
the brain mass. The dorsal antenna, consisting of a bundle of setae, 
protrudes out of a tubule situated above the brain and a little to the 
right of the median line ; lateral antennae of similar form are also 
present and asymmetrically placed ; the right lateral antenna protrudes 
low down on the side, near the posterior edge of the lorica, and the 
left is placed higher up nearer to the centre of the side, as shown in 
the figures. The antennae and their position are best seen when the 
animal slowly revolves on its longer axis, they then come into view 
one after the other. The male is not known. 
Size 1/250 to 1/150 in. Habitat: reservoir, Dundee (Hood, 
Caiman) ; large lake of Plon, Holstein (Zacharias). 
( Ecistes brevis sp. n. Hood. PI. VII. fig. 4. 
Corona slightly oblong, body and foot stout and short, ventral 
antennae stout and of moderate length ; oral aperture prominent ; 
tube soft, gelatinous, roughly made. Eyes absent in adult, but 
present in the young. 
