1 88 2.] Recent Literature. 233 



which is regarded as a sub-order of Thysanura, while the recent 

 views of Semper and Moseley as to the formation of coral reefs 

 are briefly referred to. The index has been altered to correspond 

 with changes in the text. 



Verrill's Cephalopods of the Northeastern Coast of 

 America 1 . — This is a memoir of 267 pages.with 44 plates, upon the 

 species of Cephalopods which have been collected upon the Atlantic 

 coast of the United States, mostly within a few years, by the 

 United States Fish Commission and the United States Coast Sur- 

 vey. It is a monographic account of these animals, accompanied 

 by most excellent plates from drawings by Mr. Emerton. While 

 the bulk of the work is devoted to careful descriptions of the 

 species, the gross anatomy of a number is given and illustrated, 

 and the habits of some of the common species described. Besides 

 the descriptions of gigantic squids and the excellent drawings 

 illustrating them, the point of most interest brought out by the 

 author is the description of the cone discovered by Mr. W. H. 

 Dall in MoroteutJiis robusta Verrill. It is figured on PI. xxnr,and 

 thus described by Professor Verrill : " This genus will have, as 

 known characters: A long, narrow, thin pen, terminating posteri- 

 orly in a conical, hollow, many-ribbed, oblique cone, which is 

 inserted into the oblique, anterior end of a long, round, tapering, 

 acute, solid, cartilaginous terminal cone, composed of concentric 

 layers and corresponding to the solid cone of Belenuiites in posi- 

 tion and relation to the true pen." 



This is a most interesting discovery, for we arc now able to 



which have usually been homologized with the pen or bone of 

 cuttle-fishes. The Moroteuthis is a gigantic calamary, but the 

 ordinary Belemnites may have been closely related in form to our 

 hooked calamary, and a cone three inches long may have been 

 worn by individuals not over two feet long, and not differing 

 essentially in form from our common Ommastrephes. The cone 

 is present or absent apparently in quite closely allied forms. We 

 wish the author had made a little more of a subject of so much 

 palaeontological interest. 



