REVIEWS OF NEW PUBLICATIONS. 
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series. The Corallines still are admitted in most of our zoological classifications, 
and we wish our author had entered a little into the detail of the reasons that 
have led him to adopt the views of the German anatomist. 
The history of the Polyps is commenced with the description of the Fungia 
Agariciformis, representing, according to Prof. Jones, the simplest form of this 
class. The gelatinous simple form of these animals is next considered, and a 
minute account given of the structure, functions, and mode of reproduction of the 
fresh-water Polyps (Hydros). They abound in the pools and clear streams of our 
own country. They are simply bags possessing tentacules for the prehension of 
food. They may be reproduced in two ways. The ordinary mode is by the 
sprouting of buds or gems, which in process of time leave the parent, and become 
perfect animals. Their fecundity is very great, and it is calculated that more 
than a million might be produced in a month by a single Polyp. 
The next form of these animals is the compound Cortical, which may be 
looked upon as a combination of the two preceding. The simple Polyps of the 
Hydras being placed on the gelatinous surface of the Fungia. This family is 
divided by Cuvier into three sub-families:— Keratopkytes , or those having a 
horny axis, including the Coral and Gorgonia; LitkopJiytes , possessing a hard 
calcareous axis. These are the most numerous, forming the extensive genera of 
Madrepora ; and lastly Swimmers , or those having a stony axis, but not fixed* 
including Pennatula and Alcyonium. The Lithophytes comprehend those species 
which exist in so large numbers at the bottom of the sea, and are supposed to 
have assisted in forming numbers of its islands. The above forms have internal 
skeletons; but there is a large number, forming the sub-family Tubularii of 
Cuvier, in the family Coralliferi , that are remarkable for possessing a higher 
organisation and an external skeleton. They form the class Bryozoa of Ehren¬ 
berg, 44 and have been recently designated by Dr. Arthur Farr 44 Ciliobrachiate 
Polyps.” The peculiar mode of growth of these animals is entered into by our 
author. They are remarkable for having a visible circulation, which may be 
seen by means of a good glass, and globules observed moving in different 
directions. We may observe, however, that the diagram Fig. 14, to illustrate 
this phenomenon is destitute of the arrows pointing out the direction of the 
currents. 
The next class of animals brought under our notice is the Polygastrica of 
Ehrenberg. We shall not follow our author through the interesting details of 
the history of these little beings, but proceed to advert to his remarks upon the 
labours of Ehrenberg, to whom we are chiefly indebted for our knowledge of 
these animals. It is about eight years since Ehrenberg announced that the 
vesicles observed in the interior of the Monas and other animalcules where 
really stomachs. He came to those conclusions by placing the animals in 
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