442 MR. P. H. GOSSE ON THE STRUCTURE, FUNCTIONS, AND HOMOLOGIES 
lower part of the quadrantic mass above desciibed. At the ventral extremity they 
are articulated to a fulcrum (A), which is a little bent downward. The solid 
framework of each ramus sends oif, from its inferior surface, a slender curved pro- 
cess ip), which is connected with the extremity of ihe fulcrum, and is probably the 
analogue of the alula. 
108. The action of this apparatus is as follows : — The ciliary vortices, produced by 
tlie waves of the coronal disk, pass together through the upper sinus, and are hurled 
in one stream along the centre of the face, nearly to the projecting chin. Here is 
placed the orifice of the huccal funnel, a perpendicularly descending tube of con- 
siderable width (fig. 66), slightly funnel-shaped at the top, the interior surface 
of which is strongly ciliated. It descends straight upon the mastax, over the part 
where the unci unite. But just above this point there are two valves projecting 
from the walls of the tube, also well ciliated. These can be brought into contact, 
or separated in various degrees, at will ; and being very sensitive, they regulate the 
force of the inflowing current, and doubtless exclude hurtful or useless substances. 
The current now flows along the two rami of the incus, as already described ; and, 
passing between their separated points, descends into the oesophagus, a slender duct 
opening beneath them {p), and leading into the digesting stomach. 
109. As this current passes, the manducatory apparatus acts upon the particles of 
food which it brings in its course. The quadrantic masses approach each other and 
recede, with a rapid rolling movement, in the direction of the curvature of the 
while, at the same time, the rami of the incus open and close their points, rise and 
sink, and occasionally perform a kind of shoveling action. The points of the fingers 
of the unci, meeting each other, doubtless pierce and tear the Infusoria swallowed, 
and the striated faces of the quadrantic masses bruise, squeeze, and grind them 
down. 
no. When the muscular investiture is dissolved away by potash, the essential 
identity of the whole structure with that of the type already described becomes 
abundantly evident. A comparison with Notommata clavulata, for example (compare 
fig. 71 with figs. 25 and 26), will show this. Even the mallei, which in some aspects 
present difficulty (figs. 67 and 69), when viewed vertically are but little changed : 
the fingers are parallel, instead of divergent, and the ansate character of the manu- 
brium is lost ; but three areas, enclosed by loops or carinse of solid substance (fig. 71 ), 
reveal their true nature. 
111. Another well-marked and easily recognized family, in this group, is that which 
Ehrenberg has named Philodincea, the first forms of Wheel-animals which attracted 
the notice of rnicroscopists. The buccal funnel is here rather long and slender, and 
always permanent ; the manducatory apparatus having no power of materially alter- 
ing its relative position in the body, and never being brought into contact with the 
exterior. 
112. Tl.' mastax in Rotifer macrurus (figs. 72 to 78), vvhich may be considered as 
