CHEIRURUS. ACIDASPIS. 11 



2. Cheirurus Sternbergii ? BoecJc, PI. I, figs. 14, 14 a. 



1825. Paradoxides ?, Sternberg. Verhandl. Gesell. vaterl. Mus. Bohmen, p. 85, 



pi. i, fig. 5. 

 1828. Trilobites Sternbergii, BoecJc. Mag. Naturvid., vol. viii, p. 37. 

 1843. — — Burm. Org. Tril.,E,ay Soc, p. 115, pi. iii.figs. 7,8. 



1845. Cheirurus — Beyr. Ueb. bokm. Trilob., p. 15, fig. 4. 



1846. — — Barr. Notice prelim., p. 86. 



1846. — gibbus, Beyr. Unters. itb. Trilob., pt. 2, p. 3, pi. iv, fig. 5. 



1847. — Sternbergii, Hawle and Corda. Abhand. Bobin. Gesell., 



Band 5, p. 251. 

 — affinis, — Ibid., p. 252. 



1852. — Sternbergii, Barr. Syst. Sil. Bohem., vol. i, p. 795, pi. xli, 



figs. 29—39, Etages B— H. 

 1872. — — — Syst. Sil. Bohem., vol. i ; Supplement, 



p. 94, pi. xii, figs. 8 — 15. 



A fragmentary specimen from Lummaton in my collection is, in the opinion of 

 Mr. Roberts, probably different from the Cheirurus commonly found there. In 

 this opinion I coincide; and, on the other hand, I can see no difference, as far as 

 the evidence goes, between it and Gh. Sternbergii (Boeck), as figured and described 

 by Barrande. 



The specimen consists of the upper part of a glabella. The frontal lobe is 

 short and receding, and somewhat flattened at the sides ; the frontal and median 

 furrows are oblique and shallow in the centre, and the profile is convex. In all 

 these points it differs from Gh. Pengellii, and it is, moreover, very much larger 

 than the largest known specimens of that species. 



The evidence is, however, too slight for positive identification, and it will be 

 interesting to see whether it is borne out by any specimens that may be found 

 in future. 



Cheirurus Sternbergii is the type species of the genus. It was originally 

 figured and described by Count Sternberg in 1825 from a Bohemian fossil, and 

 the name was attached to it by Boeck in 1827. It is very different from the 

 species figured under this name by Minister in 1840, and very much more like 

 Ch. Pengellii, although it disagrees with that species in numerous details. 



III. Family. — AciDASPiDiE, Barrande, 1852. 



1. Genus. — Acidaspis, Murchison, 1839. 



This genus, the only one in its family, was established by Murchison, but 

 not fully defined by him, and foreign authors have occasionally adopted the 

 alternative name of Odontopleura, Emmrich. The trilobation of the head is 



