F. R. Cowper Reed — Some Wenlock Species of Lichas. 9 



LiCHAS (DiCRANOPELTis) WooDWAEDi, sp. nov.^ (PL I, Figs, 7, 8.) 



L. Barrandii, Fletcher (pars): Q.J.G.S., 1850, vol. vi, p. 238, pi. xxvii, fig. 10 

 [non pi. xxvii bis, fig. 5). 



The description which Fletcher gave of the species which he 

 called L. Barrandii corresponds exactly with his fig. 5, pi. xxvii his, 

 and with the two specimens on which this was founded, but it does 

 not at all agree with the figure on the preceding plate (fig. 10, 

 ,pl. xxvii), nor with the specimen which it represents, and the only 

 point in the description which is borrowed from it refers to the con- 

 centric striation of the under side, which is not seen on the other 

 specimens. A suspicion that two species have been confounded 

 at once arises, and an examination of the type-specimens which 

 are in the Woodwardian Museum confirms it. Moreover, the 

 type-specimen represented in fig. 10, pi. xxvii shows only the inner 

 surface of the shell, but another showing the actual outer surface in 

 relief has come into our possession with the remainder of Fletcher's 

 collection presented in 1897, and it was labelled by Fletcher himself 

 L. Barrandii. From this material a fairly complete description of 

 this new species can be given, so far as the pygidial characters are 

 concerned. 



Pygidium broadly parabolic ; ratio of length to width as 3 : 4. 

 Axis rounded, convex, slightly elevated above side-lobes ; nearly 

 one-third the width of the pygidium at front end ; short, broad, 

 not as long as broad ; sides converge posteriorly at angle of about 

 35° ; abruptly truncated at posterior end by straight transverse 

 furrow ; bears two well-marked continuous rings at anterior end. 

 Axal furrows well-marked, nearly straight. Transverse furrow 

 defining termination of axis weak in centre, strongly impressed 

 at sides. 



Lateral lobes flattened, nearly horizontally extended, furnished 

 with six pairs of furrows of equal strength ; each lobe consisting of 

 three broad foliaceous pleuras with free falcate, backwardly directed 

 ends. First two pleurge on each side complete, and well-defined 

 by ■ strong interpleural furrows of equal depth, the first furrow 

 making an angle of about 30° with the front edge of the pygidium, 

 and the second an angle of about 60°. First pleura marked by 

 diagonal furrow which runs parallel to the first interpleural furrow, 

 but dies out before reaching the free point of the pleura. Second 

 pleura marked by similar furrow starting from axal furrow at the 

 point of origin of first interpleural furrow, and running thence 

 parallel to second interpleural furrow, but dying out before reaching 

 free point. 



Axal furrows continued backwards behind axis, at first with same 

 angle of convergence and then almost parallel to each other, but 

 -disappearing at some distance from the posterior margin of pygidium. 

 The post-axial median piece enclosed between them is narrow, and 

 slopes down rapidly to level of side-lobes. Third pair of pleurge 



1 This species is mentioned by the author in his paper on the genus Lichas : 

 Q.J.G.S., 1902, vol. Iviii, pp. 72 and 82. 



