316 
PROGRESS or MICROSCOPICAL SCIENCE. 
cell of the drum, which is formed by the first abdominal ring. Pre- 
vious observers have described an extensor muscle of the drum ; but 
the muscle has another function, as the author proposes to show in 
another paper. 
How to arrange Diatoms. — Among the many methods that have 
been devised for this purpose is one recently described in the 
' American Naturalist ' by Dr. G. C. Morris, of Philadelphia, who, 
that journal says, arranges diatoms with facility and success, by 
using the mechanical stage as a means of holding and moving the 
bristle which handles the diatoms, while the sub-stage prolonged 
upwards (through the opening of the regular stage) by means of a 
tube, serves as a stage to hold the object slide. An arm, attached by 
means of a socket to the stage, carries a small cork, through which is 
passed a needle, and the bristle is fastened to this needle in such a 
manner as to project about a quarter of an inch beyond its point. 
With this arrangement the objective can be readily focussed upon the 
bristle-point, which can then be moved in any horizontal direction, 
while the object can be brought up to focus, or depressed below it, by 
means of the rack of the sub-stage. 
Contents of Foreign Journals. 
It would be of course impossible to give abstracts of even one-tenth 
part of the total number of scientific journals that are published on 
the Continent, and that relate either fully or in part to microscopic 
labours. But at the same time we consider it most useful to give the 
contents of these journals, for then the worker will be enabled to see 
at a glance where the particular information he requires is to be had, 
and a visit to either the libraries of the Eoyal or the Linnean Society 
will at once place him in possession of the entire paper and illustrations 
upon the question in which he is interested. In fact, it will be to the 
independent researcher more valuable information than an abstract, 
which he would not probably rely on. 
Nederldndisclies Ardiiv fiir Zoologie. Edited by C. K. Hoffmann. 
Band 3rd, Heft 1st. —This contains a valuable paper on the Structure 
of the Eetina in Amphibia and Reptiles, by the Editor, with two excellent 
plates. — The Development of the Entomostraca, by P. P. C. Hoek, with 
two most excellent tinted plates, certainly vastly superior to anything 
we could attempt in this country, though the journal is published at 
Leiden. — And, lastly, on the Structure of the Synovial Membrane, by 
J. G. Van der Sluijs, which is also illustrated by a plate. 
Zeitschrift fiir Parasitenkunde. Edited by Dr. E. Hallier, of Jena. 
4th Band, 2nd Heft. — This has only one microscopical paper, by the 
Editor, " On the Eesults of Microscopic Research." It has to do, of 
course, with the subject on which the journal deals. 
Zeitschrift fiir WissenscJiaftliche Zoologie, vol. xxvi. part 2. — On the 
Chilostomous Bryozoa, by W. Repiachoff. — On the Gastrotrichous 
Rotifers, by Dr. H. Ludwig. — The Anatomy of Chcetoderma nitidulum 
(a sipunculous echinoderm), by Herr L. Graff. 
