130 Mr. Herbert Goss — A Silurian Cockroach and two Scor^yions. 



fossils were tlie oldest hioion insects, it seemed unlikely that the}', 

 or even the families or genera to which they belon<;ed, were the 

 most ancient representatives of their class. The first appearance of 

 insects on the Earth was probably contemporaneous with that of 

 land plants, and as I'eraains of this division of the Vegetable King- 

 dom had been discovered in Silurian rocks, it seemed not unreason- 

 able to assume that insects might have existed at an earlier period 

 than the Devonian. The recent discovery of the wing of a cock- 

 roach in rocks of Silurian age at Jurques, Calvados, France, no longer 

 leaves the question of the occurrence of insects at an earlier period 

 than the Devonian a matter of speculation. 



In a note, recently communicated by M. Milne-Edwards to the 

 Academic des Sciences of Paris,' M. Charles Brongniart describes 

 the wing of a species of Blatta from the Middle Silurian formation 

 of Jurques. The piece of rock containing this fossil was received 

 from M. Douville, Professor in the Paris School of Mines, in whose 

 honour this the oldest Jcnown insect has been named Falceohlattina 

 Douvillei. 



M. Brongniart states that the neuration of two species of Blatlidoi^ 

 of the Carboniferous Period — Progonoblattina Fritschii (Heer) and 

 Gerablattina fascigera (Scudder) — recalls, in a slight degree, that 

 of this Silurian wing which he describes as follows : — 



" Cette aile qui raesure 0™,03o de long a appartenu h wi Bla/tide ; le champ 

 humeral est large ; on y voit la veine humerale superieure, la veine humerale 

 inferieure qui se bifurque a son extremite ; la veine vitree ou mediaue egalemeut 

 divisee en deux rameaux ; les veines discoidales superieure et inferieure et leurs 

 divisions tres obliques qui se rejoignent a leur extremite, ainsi que cela se voit encore 

 chez certaines Blattes de notre epoque ; on pent suivre la veine anale qui est assez 

 droite et s'etend presque jusqu'au bout de I'aile, puis les veines axillaires qui lui 

 sont paralleles. Ce qui est fort remarquable et ce qui distingue cette empreinte de 

 toutes les ailes de Blattes vivantes et fossiles c'est la longueur de la nervure anale, 

 et le pen de largeur du champ axillaire." 



Although the fossil wing above described is the only fragment of 

 an insect as yet obtained from rocks of Silurian age, the recent dis- 

 covery of insectivorous animals — two scorpions — in Silurian I'ocks 

 furnishes additional evidence of the existence of insects at this early 

 period. 



One of the Scorpions was obtained by Dr. Hunter, of Carluke, 

 from the Ludlow beds (Upper Silurian) of Lesmahagow, Lanark- 

 shire ; and a preliminary description of it by Mr. B. N. Peach has 

 appeared in a recent number of '* Nature." ^ 



The second Scorpion was obtained from the Upper Silurian of the 

 Isle of Gotland, and has been named by Dr. Lindstrom PalcBophonus 

 nuncius, and described by him in a letter to M. Milne-Edwards/ 



1 Comptes rendus des Seances de I'Academie des Sciences de Paris, No. 26, 

 29th December, 1884. 



^ These Blattidm are referred to in my paper on " The Insecta of the Carbon- 

 iferous Period," pp. 169-173, of vol. xv. of the Entomologists' Monthly Magazine, 

 1878, and "The Insect Fauna of the Primary or Palaeozoic Period," Proc. Geol. 

 Assoc, vol. vi. No. 6, 1879. ^ No. 796, January 29, 1885. 



* Extract from a letter from Prof. Lindstrom to M. Milne-Edwards, Comptes 

 Ptendus of the Academie des Sciences of Paris, No. 22, 1 Dec. 1884, pp. 984-985. 

 Dr. Lindstrom states that a detailed account of this Scorpion by Prof. Thorell and 

 himself will shortly appear. 



