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REVIEWS OF NEW PUBLICATIONS. 
Division II., Nematoneura (Owen). 
1. Bryozoa. 3. Epizoa. 
2. Rotifer a. 4. Cavitary Entozoa , or Catlelminiha. 
5, Echinodermata. 
Division III., Homogangliata (Owen), Articulata { Cuv.}, Annulosa (MacLeay), Diploneura 
(Grant). 
1. Cirrhipeda. 4. Insecta. 
2. Annelida. 5. Arachnida. 
3. Myriapoda. 6. Crustacea. 
Division IV., Heterogangliata (Owen), Mollusca (Cuvier), Cyclogangliata (Grant). 
1. Tunicata. 4. Gasteropoda. 
2. Conchifera. 5. Pteropoda. 
3. Brachiopoda. 5. Cephalopoda. 
Division V., Vertebrata (Cuvier), Myelencephala (Owen), Spiecicerebrata (Grant). 
1. Fishes. 3. Reptiles. 
2. Amphibia. 4. Birds. 
5. Mammalia. 
In commencing his description of the animal kingdom our author endeavours to 
settle the question, “ What is an animal ?” But he rather singularly constructs 
a definition, to which his first group of animals is an exception; he says :— 
“ The best description of an animal, as distinguished from a vegetable, which has yet been given, 
is, that whereas the latter, fixed in the soil by roots, or immersed perpetually in the fluid from 
which it derives its nourishment, absorbs by its whole surface the nutriment which it requires; the 
animal, being in a greater or less degree capable of changing its position, is provided with an 
internal receptacle for food, or stomachal cavity, from which, afte? undergoing the process of 
digestion, the nutritious matter is taken up. But in the case of the Sponge no such reservoir is 
found; and in its place we find only anastomosing canals, which permeate the whole body, and 
convey the circumambient medium to all parts of the porous mass.”—p. 13. 
We think a better definition would be that a vegetable is a being deriving 
nourishment by absorption from an external medium in which it is placed, whilst 
an animal is a being deriving nourishment from a medium that is previously 
introduced into its system. A simple definition will not, however, in all cases 
enable us to distinguish the objects of one kingdom from those of the other; and 
an aggregate of the structure and functions in the lower tribes of beings can alone 
enable us to draw a correct conclusion. The Sponges ( Poriferoe ) were at one 
time supposed to belong to the vegetable kingdom; but are now generally 
admitted amongst animals. An interesting account of their reproduction is given 
by our author, for which, and in fact for nearly all our knowledge of the functions 
of Poriferoe , we are indebted to Prof. Grant. 
The next class of animals considered are the Polyps , the principal forms of 
which are minutely described in an interesting manner. Mr. Jones, we find, 
adopts the views of Schvveigger on the nature of Corallines, looking upon them 
as members of the vegetable kingdom, and rejecting them from the animal 
