138 NOTICES OF NEW BOOKS. 



confirmed, and which was proposed by Professor Owen. The 

 Bellerophon is figured as allied to the Argonaut. It is worthy of 

 remark that the Aptychus, well known in the Kimmeridge clay, 

 and much more abundant in the somewhat newer Solnhofen beds 

 of Germany, is spoken of under the name of Pseudo-Ammonites, 

 and it is mentioned that the great desideratum is to find these 

 fossils in natural connection with the shells or other parts of the 

 Cephalopoda. It is, however, very frequently the case that they 

 occur within the shell in the last chamber of Ammonites ; and so 

 many specimens exist in which this is the case, that we are natu- 

 rally led to conclude that some relation between the two existed. 

 The matter, however, is still doubtful. 



The Articulata succeed the Mollusca in Dr. Mantell's arrange- 

 ment, and amongst them the Crustacea are very fully described, 

 the Trilobites occupying a large, but not an undue share of atten- 

 tion. The chapter concludes with a notice of the fossil insects 

 and spiders that have from time to time been discovered in the 

 various strata. 



The notice of fossil fishes is naturally derived, for the most part, 

 from the admirable researches of M. Agassiz, the latter pages of 

 whose " Mecherches," however, had not reached England at the 

 time when Dr. Mantell's work was passing through the press. 

 The chapter contains a short notice of such species (chiefly 

 British), as exhibit most remarkably the peculiarities of structure 

 of their class. 



An account of the Reptiles — some of the most remarkable 

 amongst which were collected under the author's own eye, and first 

 described by himself — next follows ; but it is professedly very 

 brief, since the Reptiles, as well as the Mammals and Birds, have 

 been the subjects of extended notice in Professor Owen's Reports, 

 published in the volume of Reports of the Meetings of the British 

 Association. The Iguanodon and the other Wealden species are 

 chiefly dwelt upon, but a notice is given of each of the groups of 

 fossil Reptiles in order. 



In his account of birds, the author alludes to those of the chalk 

 and Wealden district, and proposes the name Palceornis, to dis- 

 tinguish the species (allied, it would seem, to the Heron) found 

 throughout the Wealden strata. He then gives a detailed account 

 of the fossil footsteps of birds found in North America, and con- 

 cludes with a notice of the New Zealand species Dinornis. A 

 short notice of some of the more remarkable fossil quadrupeds 

 concludes this portion of the work. 



The third part of " the Medals " consists of notes of excursions, 

 in illustration of the mode of investigating geological phenomena 

 and of collecting organic remains, and it commences with some 

 instructions to the young geologist before starting on such trips. 

 The first excursion is abridged from a paper by Mr. Bowerbank, 

 on the Isle of Sheppey, and the next is also by the same gentle- 

 man, and refers to Bracklesham Bay, a well-known locality for 

 a peculiar fossiliferous sand belonging to the London clay, and 



