Geology and Natural History, 395 



made to accord with the new results published in Duncan's 

 " Revision of the genera and great groups of the Echinoidea.'*'* 



The chapter on Bryozoa is entirely rewritten by Mr. E. O. 

 Ulrich, whose numerous publications on this group have earned a 

 well merited place in American paleontology. The MonticuUpora 

 find a place among the tabulate corals (p. 103) and again among 

 the Bryozoa, but this reduplication is due to the fact that the 

 earlier pages were already in type when the chapter on Bryozoa 

 was written, and we are informed by the editor that in revised 

 editions of Nicholson's work as well as of '' GrundziXge^'' the 

 Ulrich classification will be adopted. 



The credit for having revised and practically rewritten the 

 translation of the entire Brachiopod chapter belongs to Mr. 

 Charles Schuchert. The classification adopted has been taken from 

 his '* Synopsis of American Fossil Brachiopoda^'' now in press, 

 and it is in substantial accord with the recent monograph of Hall 

 and Clarke, and with all the more advanced literature of Ameri- 

 can writers on the Brachiopoda. 



The present part closes with the first few pages of the Mol- 

 lusca, and it is to be hoped that the remaining parts will be 

 rapidly brought out, since the paleontologist dealing with paleo- 

 zoic fossils must have the whole of the invertebrates, at least, 

 before him in the discussion of almost any full fauna, and such a 

 work does not attain its best value as a text-book until it is com- 

 plete. 



American students will be particularly grateful to Professor 

 Zittel, not only for supplying them with an English translation, 

 but in allowing such liberal adjustment of the original work to 

 be made by their own specialists. The work has thus become not 

 only an English translation, but an Americanized edition of 

 Zittel's standard work. And we have also to thank the editor 

 for the skill with which he has rendered the German into excel- 

 lent English while preserving the scientific accuracy of the 

 author. h. s. w. 



3. Structural details in the Green Mountain region and in 

 eastern New York ; by T. Nelson Dale. (Extract from 

 XVIth Annual Report of the Survey, 1894-95. Part I, p. 543- 

 570. U. S. Geological Survey, Washington, 1896.)— The author 

 has here collected, mainly from the Taconic region, illustrations 

 of inclined, overturned, transverse and unequal folding, ialse-bed- 

 ding, obscuration of bedding by cleavage, differential cleavage, 

 cleavage-banding, two and threefold cleavage, cleavage along 

 fault lines, stretching, brecciation, and siliceous segregation, most 

 of which are intended as fresh illustrations of well-known geo- 

 logical principles. One of them, however, " cleavage-banding " is 

 not so familiar, and rather perplexing. At the end is an index 

 to descriptions of related structural phenomena previously pub- 

 lished by the author in other U. S. Geological Survey Reports 

 which readers interested in this branch of geology may find use- 

 ful. The paper has thirty-one diagrams, sketches and photo- 

 graphs. 



Am. Jour. Scl — Fourth Series, Vol. II, No. 1 1.— November, 1896. 



