544 Bibliographical Notices. 



portions as appeared desirable, interweaving them with other matter ; 

 hence it would be unjust to its author to consider this manual an 

 abstract of it. That work being intended to establish a new classi- 

 fication, and as a book of reference, a large portion of its ample 600 

 folio pages is occupied in giving the synonyms, in references, and in 

 discussions ; these I have omitted, but every species described in 

 that work will be found here, together with many others since dis- 

 covered. A new system of classification is seldom acceded to wholl)'^ 

 at first : that by Dr. Ehrenberg has met with its share of opponents. 

 The principal arguments respecting it will be found herein ; so that 

 the student, having both sides of the question before him, will be 

 able to arrive at a fair conclusion." 



The work is divided into two Parts. In the First, the general 

 history of infusorial animalcules is treated of, in 34 sections ; and 

 Part II. consists of their classification and description, viz. 188 

 genera, and 732 species. Ehrenberg's late work on the Infusoria of 

 the Chalk Formations* is briefly alluded to in an Appendix, bringing 

 the number of species up to 786. 



We are much pleased to find in Mr. Pritchard's volume a very 

 seasonable assistant and acceptable source of information to those 

 who feel an interest in the contributions which the microscope is 

 daily making to the knowledge of nature. 



Supplementary remarks on Mr. G. R. Gray's ' Genera of Birds' 



Since the publication of my former notice of Mr. Gray's work in 

 the ' Ann. and Mag. of Nat. Hist.' for Januar}' last, a few additional 

 observations have occurred to me. Being desirous of rendering this 

 excellent work as extensively useful as possible, by pointing out 

 those minor details which seem to require correction, I do not scruple 

 to add the following criticisms by way of supplement to my former 

 review. 



Page 12 of the ' Genera of Birds.' Dr. Horsfield's genus Eury- 

 labmis should be written Eurylamus. 



P. 72. It is satisfactory to find that the several authors who claim 

 the honour of giving a specific name to the type of Geococcyx, may 

 cease from the contention. This bird was first described by Fer- 

 nandez 191 years ago under the name of Hoitlallotl (see Ray, Syn. 

 Av., p. 158), and was recorded by Latham and Gmelin under the 

 name of Phasianus mexicanns . It will therefore now stand as Geo- 

 cocccyx mexicanns (Gm.). 



P. 80. The European species of Bonasa should be called B. betulina 

 (Scop.) instead of B. sylvestris (Brehm.J. 



P. 83. Cursorius europceus. Lath., ought, in point of priority, to 

 be called C. g alliens (Gm.). 



* Of tliis record of Prof. Ehrenberg's latest discoveries, with his state- 

 ment of the important geological inferences to be deduced from them, a 

 translation will immediately appear in the forthcoming Part of the 'Scien- 

 tific Mf.moirs.' 



