ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
317 
of the nerve-strands ; they have large nuclei and homogeneous or 
vacuolated plasma. Between them runs the nerve, and beside it two 
clear structureless pillars (giant fibres) with regular cross-branches 
connecting them. Lang calls the large cells ganglionic, and the clear 
strands water-vascular ; but from both of these interpretations Pintner 
thoroughly dissents. (3) Lang described the gradual formation of a 
terminal excretory pore, which Pintner denies. There is an opening 
only in the original last joint, and no rudiment of it elsewhere. 
Dr. Pintner gives a detailed description of Tetrarhynchus Smaridum 
from species of Smaris and Meena. 
Rotatoria. 
Rotatoria of the Great Lakes.* — Mr. H. S. Jennings has prepared 
for the Michigan Fish Commission a list of the Rotatoria found in Lake 
St. Clair and some of the inland lakes of Michigan. Of the 122 Rotifers 
named in the list, six are described and figured for the first time. The 
most abundant pelagic species are Polyarthra platyptera , Anurea 
cochlearis , and Asplanchna priodonta, in this respect agreeing with the 
conditions found in European Lakes. 
Foreign Rotifers.f — Mr. G. Western has a series of somewhat 
scattered notes on various Rotifers hitherto supposed to occur only in 
waters foreign to Britain. He brings forward cases of 12 species which 
certainly belong to the British list. He takes the opportunity of making 
some remarks as to the presence of antennae or setae, and points out that 
their apparent absence from some species was possibly due to the want 
of better objectives and more perfect methods of illumination, such as 
are at our disposal now, but which were not in the possession of the 
authors who originally described the species. The presence or absence 
of setae is a very unreliable character ; for example, there are species 
of Rotifers to be found which have them in some specimens and not in 
others. He concludes with stating some problems which he thinks are 
worthy of solution. 
Distyla spinifera4 — Mr. G. Western describes this form, which is 
apparently new. He first found it in some stuff taken on Putney Heath. 
At first sight it rather resembles Metopidia oxysternon. The species 
may be easily identified by the possession of two thorn-like spines on 
the postero-lateral angles of the edges of the ventral shield. 
Cyrtonia tuba.§ — Mr. C. F. Rousselet gives a more extended 
description and more correct figure of this interesting little Rotifer than 
was supplied by Ehrenberg, who originally described it. He finds that 
it cannot be allowed to remain in the genus Notommata , in which it was 
originally placed. It is clearly one of the Hydatinidse, and a new 
genus must be formed for its reception. The author gives a definition of 
the generic and specific characters. 
Macrotrachelous Callidin8e.|] — Mr. D. Bryce gives descriptions of 
ten species which he has not already noticed. The first five of them 
* Amer. Natural, xxviii. (1894) pp. 809-10. 
f Journ. Quek. Micr. Club, v. (1894) pp. 420 -G. 
I Tom. cit., pp. 427-8 (1 pi.). ^ § Tom. cit., pp. 433-5 (1 pi.). 
