376 Bibliographical Notices. 



ends modified on the Iguanodont plan. This form was considered 

 by the author nearly allied to Iguanodon, and to approach Hadro- 

 saurus in most points in -which it differs from the former genus. He 

 proposed to establish for it a new genus, Orthomerus, and to name 

 the species 0. Dolloi. The collection further included a tibia and 

 metatarsal bone referable to the same form. These Maastricht 

 Dinosaurs furnish the most recent known evidence of the existence 

 of the order. 



BIBLIOGRAPHICAL NOTICES. 



The MicrograpJiic Dictionary : a Guide to the Examination and In- 

 vestigation of the Structure and Nature of Microscopic Objects. 

 By J. W. Griffith, M.D., and Akthur Henfrey. Fourth edition, 

 edited by J. W. Griffith, assisted by the Rev. M. J. Berkeley 

 and T. Rupert Jones. Svo. London : Van Voorst, 1881-3. 



It is with no small pleasure that we find ourselves once more 

 called upon to announce the completion of a new edition of this im- 

 portant work. Having assisted, in the French sense of the word at 

 any rate, at the first appearance of the book in 1855, and having 

 welcomed the second edition in 1859, the completion of which was 

 saddened bv the recent death of one of the authors, and the third 



* 



edition in 1874, we not unnaturally feel considerable interest in its 

 success, and a hope that at each successive appearance it may be 

 found to have grown in usefulness as in bulk. 



In this respect the purchasers of this fourth edition will have no 

 reason to complain ; but, from the very nature of the case, it is im- 

 possible for us to say much more on this subject than that a great 

 amount of labour has evidently been bestowed upon the book, and 

 that much new information has been worked into it. The alterations 

 and new articles are necessarily so scattered through the pages of 

 a book the contents of which are alphabetically arranged, that it is 

 for the most part a vain effort to try to seize any thing sufficiently 

 striking to be worthy of special mention. One article, however, we 

 may particularly refer to, namely that on the microscopic structure 

 of rocks, for which the editor acknowledges his indebtedness to 

 Prof. Rutley. This article gives an excellent summary of the prin- 

 ciples of petrology, and is illustrated by a very nice plate of coloured 

 figures. The portions of the work dealing with the preparation and 

 preservation of objects have hardly received so much attention as 

 we should have expected ; but the article on angular aperture has 

 been remodelled so as to take up the results of recent researches 

 upon this much discussed subject, and a new article on micropho- 

 tography has been introduced. 



Prof. Rupert Jones has again attended to the revision of the parts 

 of the work dealing with the Foraminifera ; and the general treatise 



