COLURIDA. 111 
associate. The species is another of the discoveries of Mr. Hood, of Dundee. He finds 
it in sea-water, and has sent me many specimens in vigorous health.—P.H.G.] 
Length, ,1, to 74, inch; width and depth equal, about ;}, inch. Habitat. Tide- 
pools at the mouth of the River Tay (J.H.); and in Torbay (P.H.G.). 

Genus COCHLEARE, Gosse, gen. nov. 
[GEN. CH. Lorica not half the length ; foot long, annulate ; toes two, furcate. 
The two species which I include in this genus are minute and inconspicuous, but 
peculiar. The lorica is quite a subordinate feature, the parts behind this greatly deve- 
loped into what appears a very stout and long foot, of many annulose joints, terminated 
by two minute toes, on which the creature usually elevates itself, and turns as ona pivot. 
Both the species are lacustrine.—P.H.G. ] 
C. STAPHYLINUS, Gosse, sp. nov. 
(Pl. XXVI. fig. 9.) 
[SP. CH. Lorica hemispheric. 
The integument is wrinkled irregularly, and scarcely firm enough to be called a lorica. 
It is nearly circular in outline, arched dorsally, and flat ventrally, abruptly attenuated to 
the stout and long foot of four distinct joimts, ending in what looks like two acute toes 
soldered together, frequently turned up in a threatening manner. Eyes and internal 
organs dim and uncertainly discerned. I have found but one specimen, in a dyke near 
Stratford, in 1851.—P.H.G.] 
Length, ,} inch; width, 5}, inch (P.H.G.). 
C. TURBO, Gosse, sp. nov. 
(Pl. XXVI. fig. 10.) 
[SP. CH. Lorica three-sided. 
The form of the lorica may not be constant, yet the facies of this differed so much 
from that of the preceding, that, until we have more knowledge, it is well to treat them 
as distinct. The flexible lorica is nearly parallel-edged, but rises to a dorsal angle, like 
a roof; yet each of the sloping lateral surfaces consists of two planes, very slightly in- 
clined to each other. The head appears as if it had a broad hood like that of Stephanops 
chlena, but flexible, for sometimes a lobe of it flaps inward. The front is formed of 
two half-cones, ciliated on their inner faces, which approach and recede at will, making 
two vortices. A large occipital brain bears a red eye near its pomt. The toes are dis- 
tinctly furcate.—P.H.G.]} 
Length, =}, inch; width, ,}, inch. Habitat. Black Loch, near Dundee (P.H.G.). 
Family XVII. PTERODINADA. 
Lorica entire, various; corona and ciliary wreath those of the Philodinade ; trophi 
malleo-ramate ; foot wholly retractile, transversely wrinkled, jointless, toeless, ending in 
a ciliated cup ;—or foot absent. 
This is a singular group of Rotifera. Unlike all other loricate free-swimmers, Ptero- 
dinad@ possess a corona of a Bdelloidic, and trophi and foot of a Rhizotic type. The 
corona is that of Philodinada, the trophi are those of Melicerta, while the foot (when 
present) would be very like that of Gcistes serpentinus, but for its extremity. The two 
genera of which the family consists differ in the shape of the lorica, and in the foot. 
