Pictefs Treatise on Palaeontology. 299 



wise have furnished our author with some useful information 

 respecting the fossil cetacea of the valley of the Rhine, and 

 especially as to the genus Halianassa. Lastly, it must also 

 be stated, that M. Pictet would have found in Major Mitchell's 

 Travels in the interior of New Holland, the description and 

 the figures given by Mr Owen of the fossil species of Didel- 

 phis found in the caverns and the osseous breccias of Welling- 

 ton Valley. All these, however, are but slight omissions, 

 which cannot affect the general character of the work. 



Our knowledge of fossil birds is still so imperfect, that the 

 summary of it given by M. Pictet is necessarily confined to 

 the enumeration of the localities where traces have been met 

 with. A monograph on this branch of palaeontology is still a 

 desideratum; and it is to be hoped that the beautiful investiga- 

 tions of Mr Owen on the genus Dinornis, and on some remains 

 of birds from the London clay, will induce him to prosecute his 

 researches on this subject with the same success which has 

 attended all his palaeontological labours. I may take this op- 

 portunity of remarking that the Gryphus Antlquitatis of Schu- 

 bert, which, for a quarter of a century, has been considered as 

 a vulture of colossal dimensions in all manuals, was, in fact, 

 founded on the fossil horns of the rhinoceros. 



The second volume of M. Pictet's treatise commences with 

 the history of fossil reptiles. We have here, for the first time, 

 a systematic summary of all the investigations relative to the 

 fossil remains of these animals, which, as the author justly 

 remarks, exhibit such extraordinary forms in some of the spe- 

 cies, such gigantic dimensions in others, and a distribution so 

 different from that which obtains at the present day, that they 

 must necessarily attract. In a very high degree, the attention both 

 of geologists and zoologists. M. Pictet insists, with great reason, 

 on the complete absence of reptiles in the primary [Transition] 

 period. Their appearance at the commencement of the secondary 

 epoch, seems to me to be the most prominent character to which 

 recourse can be had, in the arrangement of primary [Transition] 

 and secondary formations in more extensive groups. I cannot 

 subscribe to the opinion of the English geologists, who include 

 the Permian system among the Palicozolc formations. The ge- 

 neral view given by M. Pictet of the succession of reptiles is 

 very well conceived : he places in a very clear point of view 



