REVIEWS AND BOOK NOTICES. 58 
presented, we think the author has demonstrated, in the clearest 
manner, that the Brachiopods are worms. And we congratulate 
ourselves that this important discovery of the obscure relationship 
of these animals has been made by an American naturalist, with 
the advantages presented in this country. 
Still, from the facts so clearly set forth, we doubt whether the 
Brachiopods should, even with all the important'Chætopod charac- 
ters they present, be included in the division of Chætopod worms, 
but rather look forward to their being united with the Polyzoa in a 
division equivalent, perhaps, to the rest of the worms, at least the 
Chætophora and Discophora combined, and forming a somewhat 
parallel group. The Brachiopods, certainly, from Prof. Morse’s 
own showing, have not either such a nervous system, Or respira- 
tory or circulating organs, or an annulated body, as would warrant 
their union with the Chetopods. He has fully proved that they 
are a synthetic type, combining the features of different groups of 
worms and other articulate animals, and in doing so he virtually 
forbids our sharing his view as to their special Cheetopod nature. 
We would prefer, in speculating on their ancestry, to derive the 
Brachiopods and Polyzoa from a common vermian ancestry, not 
much higher than the Rotifers, from which sprung two stems; one 
resulting in the Polyzoa, and the other in the more highly and 
specially-developed Brachiopods, while the Cheetopods were prob-. 
-ably derived independently from an ancestry higher perhaps, but 
vaguely resembling the Rotifers. As to the molluscan affinities 
of these animals, let those prove them who can, after. going over 
step by step the track revealed by the patient. and toilsome re- 
searches of our author. 
NORTH AMERICAN Grassnorprers.*—Dr. Hayden proposes to 
collect, in a single quarto volume, papers upon the zoology and 
botany of the Rocky Mountain region explored by him in his gov- 
ernment surveys. The fishes and reptiles will be elaborated 
by Professor Cope, the botany by Professor Porter, Hemiptera 
by Mr. Uhler, Coleoptera by Dr. Horn, birds by Dr. Coues and 
mammals by Professor Gill. The first part, on a portion of the 
Orthoptera, is now published, and if the whole work is executed 
upon the same scale, one volume cannot contain it all: let us hope 
that it will not. In the part before us, Dr. Thomas does not 
"Report of the U.S. Geological Survey of the Territories. F. V. Hayden, Geologist 
in charge. Vol. v, Zoology and Botany. Part i, Synopsis of the Acrididæ of North 
America, by Cyrus Thomas, Ph.D. 4to. pp. xX, ashington, 
