100 BRITISH PALiEOZOIC PHYLLOCARIDA. 



British. 8. A. ovata, sp. nov. PI. xv, figs. 4 and 5. Ovate. Middle Silurian. 



— 9. A. Salteri, H. "W. PI. xvii, fig. 6. Suboval. Upper Silurian. 



— 10. A. suhquadrata, sp. nov. PL xv, fig. 20. Subquadrate. Lower Silurian. 



— 11. A. angulata (Baily). PI. xv, fig. 19. Oblate. Lower Silurian. 



— 12. A. ohlata, sp. nov. PI. xv, figs. 21, 18, 23. Deeply oblate, wide. Middle Silurian. 



No Goniatites have been found with any of these. 



We propose in the first place to propovind the characters and history of 

 Barrande's typical species A. prima, no exact representative of which we have 

 yet met with in Britain. 



1. Apttchopsis peima, Barrande, 1872. Woodcuts : Fig. 7; and Fig. 10, p. 109. 



Apttchopsis peimtjs, Barrande. Silur. Syst. Centre Boheme, vol. i, Supplem., 



1872, p. 457, pi. xxxiii, figs. 1 — 21 [A. prima, 

 var. secunda, &c.]. 

 — — Romer (after Barrande). Leth. Geogn., 1876, pi. xix, 



figs. 3 a, 3 6. 

 A. PEIMA et var. secuitda, T. R. J. and H. W. Geol. Mag., 1884, pp. 349 and 354. 

 — — — Eeport Brit. Assoc, for 1884 



(1885), pp. 79 and 89. 



Aptychopsis prima includes, according to M. Barrande {op. cit.), round, 



subcircular, oval, and obovate forms of the tripartite shield-like test, which both 



Barrande and H. Woodward termed Aptj/chojysis independently in 



in the same year (1872). Among the figures (when completed in 



outline) on pi. 33, of ' Syst. Sil. Boheme,' vol. i, Supplem., 



circular or subcircular forms are represented by figs. 1 — 9, 13 — 15, 



and 18; and more or less obovate tests by figs. 11 (obovate); 10, 



Fig. 7.— spe- 12, 16, 19 — 21 (broad-obovate) ; and 17 (ovaJ). Thus there are 



chop^is °^ prwm ^^ur somewhat different shapes among these figures. 



BuWiu' Boh^ -"-^ ^^^ British Museum (Natural History) are some specimens 



B'-'tTh'Mu'^ir'" labelled by M. Barrande many years ago, as " Aptychus ? primus 



(I, 2587) " and " Aptychus ? secundus (I, 2588)." The former, when 



perfect, with the two lateral moieties and the frontal (cephalic or rostral) piece 



in place, were broad-obovate (woodcut. Fig. 7) ; and the latter (when perfect) were 



nearly or quite round. Evidently our deceased friend had decided to group, 



these two kinds together, by the time he published the Supplement of the 



first volume of his great work treating of these and other Crustaceans. The 



circular shields found in Bohemia are chiefly from the schistose or slaty mudstone 



of Borek, with some from Litohlow and Kozel, — all in fitage " B, el " ; and the 



