NOTICES OF NEW BOOKS. 133 
an illustration the Arthropoda are subdivided into (1) Crustacea, 
(2) Onychophora—Peripatus only, (83) Myriapoda, (4) Insecta, 
(5) Arachnida. Each group is represented by an individual, of 
which a complete and exhaustive examination is made, so that a 
series of analytical types afford a clear insight into the real in- 
wardness of the classification. Thus Brachionus rubens is made 
a representative of the Rotifera, and a Cockroach (Periplaneta 
americana) is used to focus the structure of the Insecta; and in 
this way if the student is unable to obtain the identical species for 
examination, an allied form will easily be procurable, and will 
serve a similar purpose. In Aves, which form Class V.* of the 
phylum Chordata, the Common Pigeon (Columba livia var. domes- 
ticata), is chosen as the subject for demonstration. ‘The whole 
class is divided into two subclasses—ARCH@ORNITHES (Mesozoic 
birds) and Nrornirues. The last form two divisions: Ratite— 
flightless Neornithes, including Emus, Cassowaries, Rheas, 
Ostriches, &c.—and Carinate, in which, ‘‘ with the exception of 
some flightless species, the sternum has a keel,” &c. The classifi- 
cation thus runs from the Emus, Cassowaries, Moas, Ostriches, 
and allied forms now extinct and in the domain of paleontology, 
through the Divers, Petrels, Herons, Ducks, and Geese, when we 
reach the Accipitres. Then follow Galline, Gralle, Gavie, 
- Limicole, Pterocletes, Columbe, Psittaci, and we arrive at the 
Owls (Striges). After these Picariz, when the system ends with 
the Passeres. Whatever may be the opinion of ornithologists as 
to this arrangement, they will doubtless agree with the authors 
that—‘‘In respect of range of structural variations, the entire 
class of Birds is hardly the equivalent of a single order of Rep- 
tiles. Among existing Birds the Emu and the Raven, which may 
be said to stand at opposite ends of the series, present nothing 
like the anatomical differences to be found between a common 
Lizard and a Chameleon, or between a Turtle and a Tortoise.” 
The chapters at the close of the second volume are devoted to 
those topics which interest all zoologists, and prove a charm to 
mostreaders. On the subject of “‘ Distribution” excellent point is 
made by the comparison of the faunas of Great Britain and New 
Zealand. These two insular areas are not widely different in size, 
have each a temperate climate, a physiography of considerable 
** In error styled Class VI. in text, vol. ii. p. 350. 
