1879.] 29 



state of preservation, and is apparently about the size of convolvuli. 

 Sjihinx SnelJenl is especially interesting as being — if we except Palcs- 

 ontina ooUtica — the most ancient fossil Lepidopterous insect known. 

 I hai'e not seen the figure of the second species, Pseudosirex Darwini, 

 and cannot, therefore, offer any suggestion as to the probability of the 

 insect being Lepidopterous. 



Having, in the two parts of this paper, enumerated the principal 

 families and genera of the Insecta of the Jurassic Period, it remains 

 for me to refer briefly to the leading types of animals and plants with 

 which they were correlated. 



The Arthropoda are represented by Crustacea — including Ostracoda, 

 and many forms of Decapoda, which last had now become the dominant 

 Order of the class — hj Arachnida* and. probably by Mj/riopoda ;t though 

 I am not aware that any traces of the last-named class have been 

 recorded. 



Of the Mollusca, the Brachiopoda, although common, are less 

 abundant than in some of the Palaeozoic Eocks. The Lamellihranch- 

 iata and Gasteropoda are also numerously represented ; and the 

 Cephalopoda are extremely abundant throughout the Period, and in- 

 clude some of the most characteristic fossils. 



The Vertehrata are represented by all the existing classes. The 

 dominant class of the Period — the Peptilia — comprises a great variety 

 of species, some of which are allied to forms now in existence, and 

 others to extinct types. Existing forms are represented by Chelonia, 

 Lacertilia, and CrocodiUa ; and extinct forms by Plesiosauria, Ptero- 

 saur ia, Ichthyosauria, and Deinosauria. 



The birds are represented by one species— the celebrated 

 Arclueopteryx macrura,^ of the Solenhofen Slate — which, with the ex- 

 ception of the traces of supposed bird foot-prints in the Triassic rocks 

 of the Connecticut Yalley, furnishes the earliest evidence of the 

 existence of this class. 



The Mammalia are represented by several small Marsupials, the 

 majority of which appear to have been insectivorous. 



The land-flora of the Period consisted chiefly of Ferns, Cycads, 

 and Conifers ; some remains of Endogenous plants have also been 

 discovered, but no Angiosperms appear to have been yet in existence. 



Surbiton Hill, S.W. : SOth May, 1879. 



* " Catalogue Systdmatiqne de la Collection Paleontologique du Muste Tej'ler," p. 83. 1876. 

 t " The Ancient Life-History of the Earth." by Prof. H. AUeyue Nicholson, p. 233. 1877. 

 { Two or more specimens of this species have been discovered, but only one of them has, I 

 believe, yet been described. 



