309 
Huzleyi. The swarm spores of these species, when they 
leave the parent cyst, are pear-shaped, with a single long 
hair-like flagellum, by the lashing movement of which they 
swim about. After a time they settle, whereupon the fla- 
gellum becomes an ameceboid process. These are merely 
cytods, but the same phenomenon has been observed in the 
case of swarm spores with a nucleus, 7.e. real cells, and de- 
scribed by De Bary, in his monograph of the Myxomycete. 
The same thing was seen in the epithelial cells of sponges 
of the order Leucosclearia by Professor Haeckel, whilst at 
Bergen, in-Norway, in August and September, 1869. But by 
far the most interesting observations of the Professor on this 
subject are those made in the Canary Island Sanzerote. 
Here he has been able to observe the direct origin of the 
motus ciliaris from amceboid protoplasmic movement, first, in 
the spherical masses arising from the division of the egg in 
the Siphonophora ; secondly, in a new and very remarkable 
form which he has discovered, and which he alls 
Magosphera Planula, and considers to represent a new and 
separate group of the kingdom Protiste. This creature has 
a ball-like body, consisting of pear-shaped cells, bedecked 
with many cilia. These ciliated cells not only can be seen to 
develop out of ameeboid cells, but also subsequently to resume 
that condition. For after the ciliated ball has swum about 
for some time, its component ciliated cells separate from 
one another, and gradually pass into an ameba form. 
These observations of Professor Haeckel are not only of 
importance as confirming physiological results, but also of 
classificatory value, as showing that their possession of cilia, 
as opposed to the exhibition of an amceboid movement, 
must not any longer be considered as a ground for 
placing the Infusoria in a separate group.— Academy. 
Histological Classification. Rollet has published [‘ Unter- 
suchungen aus dem Institute fiir Physiologie in Graz,’ 1871, 
2tes Heft, p. 111; ‘Centralblatt, No. 20, 1871, p. 308] 
a valuable paper on the discrimination of elementary parts 
and tissues. In the first part Rollet opposes the rigid dis- 
tinction lately introduced by E. Hackel between cells and 
cytods, as well as the theory of the same writer relative to 
the homogeneousness of protoplasma. In the second part he 
develops the principles which should be made the basis of a 
scientific classification of tissues, and criticises the systems of 
Henle, Frey, Beale, Kolliker, Leydig, and Hickel. Rollet’s 
own system claims to be founded upon physiological expe- 
rience. He adopts the views of His relative to the distinc- 
