AND TWELVE NEW SPECIES OF ROTIFERA OF THE ORDER BDELLOIDA. 371 
Microdina, n. gen. 
Toes, four. Yolk-mass with four nuclei. Gullet very short. Teeth, three or four 
on each side, at anterior end of jaws. 
The terminal cilia of the gullet, which project a little way and assist in seizing the 
food, might be regarded as constituting a rudimentary corona. It is not usual, how- 
ever, to regard the end of the gullet in a Philodine as part of the corona, that term 
being restricted to the discs and the two wreaths. It seems, therefore, more correct to 
consider Microdina as having no corona. 
The parts of the jaws are movably articulated, not rigidly united as in other 
Bdelloids. The rami have large curved processes on the ventral side. The manubrii 
may have no loops, or may have from one to three, more or less distinct. 
In Philodinadee and Adinetadee the larger teeth cross about the middle of the jaw, 
and there are finer strize towards each end. In Microdinadee the large teeth are all at 
the anterior end, and fine strize only cross the posterior half of the Jaws. 
Owing to the shortness of the gullet, the jaws are close to the mouth. 
Microdina paradoxa, n. sp. (Plates I. and IT.) 
Specific characters.—Of moderate size, stout, enlarged at level of mastax and at 
posterior part of trunk, contracted between those parts. Cisophagus and large 
granular mass connected with it, of a bright crimson colour. Stomach voluminous, 
its walls filled with coloured globules. Foot of three joints. Spurs short, stout, 
somewhat bottle-shaped, a broader basal portion contracting into a narrower apical 
portion, obtuse, separated by narrow convex interspace. Toes large and thick, the 
ventral pair much larger than the dorsal. Foot-glands forked. Antenna two-jointed, 
flattened. Oviparous. 
General description.—Greatest length ;}5 to gy inch. Always fiddle-shaped, 
owing to the narrowing between the head and the enlargement of the trunk. The 
position of the posterior enlargement varies. When an egg is carried, the broadest part 
will be in the second or third central segment. When there is no egg and the ovaries 
are undeveloped, the fourth central or pre-anal may be broadest. The rostrum differs in 
no way from that of a typical Philodine. The mouth is small and somewhat trifoliate. 
The lower lip is of the V-shape usual in the order. The upper part is obscurely two- 
lobed. The sides of the mouth are finely longitudinally striate. ‘he whole animal is 
sometimes pale rose-colour or purple. More generally it is colourless, except for the 
erimson gland and cesophagus, the stomach and the egg. The globules in the stomach 
walls vary greatly in colour. They have been seen red, yellow, greenish, orange, 
magenta, sienna, or umber. ‘The two last colours are commonest, and are used in the 
illustrations. The ege is of a tawny yellow. A clear fleshy mass fills the head 
