BRITISH FOSSILS. 



5 



least, the second or third not being at all visibly enlarged at the 

 end.* 



The pleurae are wider than the axis by one-fifth, or less, and are 

 but slightly curved, the tip acuminate, short, recurved, but not 

 jDroduced as in P. Davidis. We have only eight plenrse, a.nd 

 cannot therefore determine the shape of the extremities of the 

 hinder ones. But there is no appearance of enlargement in the 

 seventh or eightli. The groove is very oblique, and runs into the 

 short mucro, rather than ends abruptly behind its base. As M. 

 Angelinas P. Forchhammeri wants the front body rings, and ours 

 the hinder ones, it is not possible to institute a closer comparison. 



Although very incomplete, enough remains to show that the 

 species is distinct from any of the Bohemian ones, unless it may be 

 P. Bohemicus, and from either of the three Swedish species described 

 by Angelin, except P. Forchhammeri. 



But there are several points in which it rigrees with the latter 

 species and differs from P. Bohemicus. The glabella is widely 

 clavate, and the furrows across the base are parallel, or nearly so. 

 The eye appears to be nearly in the right position, but this is 

 obscure. The body rings, of which we have only 16 preserved, 

 have the axis narrov»^er than the pleurae, and the latter have only 

 short points, and very oblique grooves. The second pleura is not 

 elongated, nor at all wider than- the third, another point in which 

 it differs from P. Bohemicus, but in which P. Forchhammeri does 

 not offer means of comparison. But in the proportionate length to 

 their width, the pleurae agree much better with the Swedish species, 

 the length being rather more than three times the width, while in 

 P. Bohemicus it is rather less. 



In both P. spinosus and P, rotundatus of Bohemia, and P. 

 Tessini of Sweden, the two basal glabella furrows, besides the neck 

 furrow, run quite strongly across. Our species does not need, 

 therefore, comparison with them, as it has only one transverse 

 groove above the neck furrov/ ; the rest are very obscurely indi- 

 cated in this specimen, which has been much compressed in an 

 oblique direction. This will account for the narrow glabella. 



Locality and Geological Position. — Lower Lingula Flags, 

 North Wales (exact locality uncertain, probably near Dolgelly). 

 Collected by A. Selwyn, Esq., 20 years back. (Mus. P. Geology.) 



* Usually Bohemian species have the second ring- enlarged. N. American species the 

 third pleura. In Anopoknus, an allied genus, the hindermost 3 or 4 are all enlarged. 



