Apsilus and other American Rotifer a. By Dr. A. C. StoJces. 273 
On both sides of the intestine is a pyriform gland composed of 
a mass of nucleated cells, each gland apparently emptying into the 
larger lateral diverticulum (m, fig. 2). Under Apsilus lentiformis 
Metsch., Dr. Hudson says,* “There are two pear-shaped glands 
attached by their narrow ends to the crop.” I have not been able 
to see that the pyriform glands of A. hucinedax are so attached. If 
there is a duct from each gland to the proventriculus, which has the 
position of the crop in the other Flosculariidae, it must be about half 
as long as the entire body. I have at times thought, however, that 
I could observe such a duct, but the appearance seems to be caused 
by a long ribbon-like muscle directly above each gland. If the parts 
do empty into the proventriculus, then they must be secretory ; if 
into the intestine, excretory — a difference of considerable importance. 
The contractile vesicle (cv, fig. 2) , opens directly into the cloaca 
through a plainly visible circular aperture. It is similar to that de- 
scribed in A. lentiformis Metsch., likewise sending off a single large 
trunk which divides into two branches, each passing obliquely toward 
the front, and terminating in a cluster of long loops surrounded by a 
granular material, and with branches and vibratile tags in the anterior 
body, and a somewhat complicated system of canals in the walls of the 
coronal cup. The lumen of the main cup and of the primary branches 
is not clear and open, but is obstructed by what seem to be irregular 
membranous folds of the inner walls. The fluid of the contractile 
vesicle is finally expelled into the external water through the anal 
aperture, which is always imperfectly closed, and is surrounded by a 
sphincter-muscle about 1 /3000 in. broad. 
The whole inner surface of the coronal cup is densely hispid, but 
after careful and prolonged examination I have not been able to find 
the slightest trace of cilia. All the setae are fine, short, recurved, 
and absolutely rigid and immobile. 
The entire front surface of the body, the basal region circum- 
scribed by the coronal cup, is likewise densely hispid ; but in addition 
to the short setae, this surface exhibits numerous rounded, cushion- 
like elevations, each armed with a broad fan-like cluster of long- 
immobile setae, those at the lateral borders (figs. 1 and 2) being 
especially long and conspicuous, measuring about 1/900 in. in length. 
After extended and careful examination of this region also, I feel 
entirely safe in saying that there are no cilia present within the 
coronal cup ; even the fine setae clothing the coronal surface of the 
oesophageal ring, where their presence might be anticipated, are 
absolutely rigid and motionless. 
I have seen food taken in more than one instance, the Infusorian 
Halteria grandinella Mull, being the victim in each instance. The 
coronal cup is exceedingly sensitive ; at the slightest touch of a 
floating object it is quickly tilted in the direction of the delicate blow 
‘ The Rotifera,’ i. p. 58. 
