- the active animal their rapid motion suggests the existence 5 
1082 Notices of some new Parasitic Infusoria. [November, 
mass with a carelessness as to results quite in keeping with its — 
bulk. It measures from 43, to ¿p inch in length. 
On account of the color it may be named Opatina flava, and 
the following description, in connection with its habitat within 
the rectum of the rarest of our batrachians, will probably be 
sufficient for its identification. It is shown in Fig. 1 magnified 
about 235 diameters: 
Opalina flava, sp. nov.—Body ovate, inflated, often as long as broad, or subpyri- 
= orm, widest and rounded posteriorly, the length once and 
one-half to twice the breadth ; the right and left hand bor- 
ders evenly rounded; striations of the cuticular surface 
obliquely disposed and bearing the long, fine, vibratile cilia; 
nuclei (?) numerous, small, scattered ; sarcode enclosing many 
refractile corpuscles and larger spherical bodies apparently 
X 235 vacuolar ; contractile vesicle none; parenchyma lemon-yellow, 
Fic. 1.—Ofalina the color darkest near the periphery, where it is disposed in a 
flava, sp. nov. layer, the central portion of the sarcode being comparatively 
colorless. Length, 7}, to sty inch. Habitat, the rectum of the spade-foot hermit 
toad, Scaphiopus holbrooki. 
The intestinal fluid seemed thickened by the throng of bacteria, 
bacilli, vibriones and spirilla accompanying the Opalinæ; and 
associated with them was not only the undescribed flagellate 
zooid to be referred to presently, but a large species of Opalina,. 
which I have, after some hesitation, identified with 0. eat 
Purk. Their appearance and structure are those of the latter, 
but the size is much less. They are quite active. AS they 
pressed each other beneath the surface or forced each other af 
ward, the aspect of the field of view was comically like a pool 
furiously boiling soup with big dumplings bobbing about. 
Associated with this crowd was a somewhat more a 
flagellate infusorian. It, in common with most endoparasites, 
colorless, and very soft and flexible. Its structure 15 50 differe® 
from all other creatures in so many particulars that a new ae 
is needed to receive it. In its habitat it seems restricted Hi ee 
rectum, Very seldom, if ever, is it captured wandering e i 
upper intestine. Its form is more or less ovoid, usually par 
to a somewhat pointed anterior extremity, and its consis pe 
seems scarcely greater than the white of an egg. The we 
terior vibratile flagella, about equaling the body in nae ne 
-extreme tenuity, their three-fold aspect appearing only 4 In 
Most careful scrutiny of the weakened or dying infuso i of 
