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dean elytra of the Stonefield slate, which is stated by Professor 

 Westwood to be " decidedly tropical." Probably Mr. Scudder is 

 somewhat prejudiced by the opinion which has, according to M. 

 Preudhomme de Borre, always prevailed amongst Continental 

 Naturalists, viz., that the order Lcpidoptera was the last created, 

 and that none existed prior to the Tertiary epoch. I believe that 

 the same opinion is also held by such English entomologists as 

 have given the subject their attention. Sir John Lubbock, F.R.S., 

 in his " Origin and Metamorphoses of Insects," observes, " "Well 

 characterized Ortlwptera and Neuroptera occur as early as the 

 Devonian strata ; Coleoptera in the coal measures ; Hymenoptera, 

 Hemiptera and Diptera in the Jurassic; Lepidopkra, on the 

 contrary, iwt until the Tertiary" M. Oustalet appears to fonn an 

 exception to Continental Naturalists, in his view of the probable 

 date of the apparition of the Lepidoptera on the Geological 

 Horizon. At page 2G of his "Recherches sur les insectes fossiles," 

 he gives the Upper Oolite (Epoque de Purbeck) as the period 

 during which this order first appeared. Since the date of the 

 discovery of P. OoUtica, another fossil butterfly is stated to have 

 been discovered in the Stonesfield slate of Oxford. This second 

 specimen is said to be in the possession of Mr. Parker, of Oxford, 

 but has not yet, I believe, been figured or described. 

 Lias and Rhcetics. 

 The Lias, including theiein the Rlioetic series, is in thin 

 cmmtry the lowest formation of the secondary rocks in which 

 fossil insects have been detected. It is of great extent in this 

 country and generally rich in remains. It consists of Argillaceous 

 limestones, shell, marls, and clays, and is in England divided into 

 three formations, viz., the Upper, Middle, and Loiver, and is for 

 the most part of marine origin. Sir Charles Lyell states that 

 some members of the series, especially in the lowest part of it, 

 have an estuarine character, and must have been fonned within 

 the influence of rivers. In some sections of this formation insect 

 remains have been detected in such abundance that the beds 

 containing them have, as in the Purbeck strata, been called the 



