532 S. H. Scudder — On a Neio Fossil Butterfly. 



The following differences of character will distinguish this species 

 from Necrocarcinus tricarinatus : — 



Orithopsis. Necroearcin tis. 



Eostrum bifid. Eostrum acute, triangular. 



Orbits looking forwards ; orbital lobes Orbits open above ; orbital lobes rather 



well produced. small. 



Antero-lateral border with acute spines, Antero -lateral border with short, stout 



of which the metabranchial is the spines, of which the mesobranchial 



largest. is the largest. 



Width of orbito-fi-ontal region not ex- Width of orbito-frontal region exceeding 



ceeding half the greatest width of half the greatest width of carapace. 



carapace. 



Large dorsal tubercles indistinct. Large dorsal tubercles distinct. 



n. — Dksoeiption of a New Fossil Butterfly ^ {^Satyrites 

 Betnesii), found at Aix in Pkovence. 



By Samuel H. Scudder, Esq., of Boston, U.S. 

 (PLATE illl., FIGS. 2 and 3.) 



DUEINGr a recent visit to the Marseilles Museum, and while 

 examining the rich collection of fossil insects preserved there, 

 my attention was attracted by two specimens of the remains of a 

 fossil butterfly. Although not very well preserved, nor indeed so 

 perfect as the specimen of a fossil butterfly from the same formation, 

 which was described thirty years ago by Dr. Boisduval, it was 

 evident, at first sight, that the remains in question belonged to a 

 different species, since the lateral moulding of the principal wings 

 was very much inflated. 



No similar form having to my knowledge been described from the 

 formation in which this was found, Dr. Eeynes, the eminent 

 Director of the Museum, courteously placed in my hands the best 

 specimen, so that I might examine it niore attentively. The second 

 specimen is very imperfectly preserved, but nevertheless it un- 

 doubtedly belongs to the same species. 



The fossil is the natural imprint of a butterfly — the insect being 

 placed on its side, with the wings elevated one against the other, 

 the legs spread out as if it were suspended, the spiral proboscis im- 

 rolled, and the antennae lowered in the same direction as the legs. The 

 first wing on the right, which is found underneath, is slightly 

 turned up and disturbed along its margin, which shows that the 

 specimen has undergone great maceration in quiet water, before 

 being covered up by the deposits which have preserved its most 

 essential features. The condition and the position of all the parts 

 of the fossil lead us to conjecture that it has been carried away to 

 its fixed place of repose by a feeble current, which has left its most 

 slender organs in the direction which it took. 



It is evident that the object in question is an imprint, for the 

 mouldings of the upiDcrmost wing are imprinted in a hollow like 

 those which may be observed in the upper part of the wings of the 

 living Satyrides, whilst those on the wing which is below are re- 

 produced in relief, as may be observed on the lower surface of the 

 1 Translated from the " Eevue et Magasin de Zoologie," 1872. 



