Vol. 69.] PAHADOXIDES FROM KEY e's CASTLE. 45> 



4. Two Species of Pabadoxwes from Neve's Castle (Shropshire). 

 By Edgar Sterling Cobbold, F.G.S. (Read December 4th,. 

 1912.) 



[Plate 17.] 



A number of trilobites, collected for H.M. Geological Survey by 

 Mr. T. Rhodes in 1892 from Neve's Castle and Comley (Shrop- 

 shire) have been submitted to me for study and identification by 

 Prof. Charles Lap-worth, under whose direction they were obtained. 



Among these are two species of Paradoxides, from a dark 

 flaggy limestone at Neve's Castle, that seem of special interest as- 

 representing forms well known elsewhere, but not hitherto noted 

 from Shropshire. 



The material available for description consists of a number of 

 fragments of head-shields, several free cheeks and pleura?, a few 

 hypostomas and two pygidia. Almost every specimen has been 

 subjected to a certain amount of distortion, and some have been 

 crushed to a mosaic of small pieces, so that the natural convexity 

 is lost. But the specimens are otherwise beautifully preserved : the 

 tests, where unweathered, are intensely black, and show the delicate 

 surface-characters excellently. 



Paradoxides bohemictts Bceck, var. salopiensis, nov. (PI. 17, 

 figs. 6-17.) 



J. de Barrande, 'Syst. Silur. Boheine' vol. i (1852) p. 367 & pi. x. 



The fragments on which this variety is founded, taken together, 

 indicate a close agreement with Barrande's description and figures, 

 and with some Bohemian specimens which, through the kindness of 

 the Keeper of the Geological Department of the British Museum 

 (Natural History), I have had the opportunity of studying. There 

 are, however, the following divergences, which are constant : — 



(1) The eye -lobe is proportionately longer. 



(2) The posterior branch of the facial suture is concurrent!}- shorter, 



and its general course is less steeply inclined to the posterior 

 border. 



(3) The free cheek is proportionately shorter and wider, and has a 



slight intra-marginal ridge. 



(4) The points of the pleurae are more slender. 



(5) The pygidium is more quadrate in outline, and has only two- 



annulations on the axis apart from the articulating facet. 



The cranidia figured (PI. 17, figs. 6, 8, 9, & 12) are from 13 to 

 26 mm. long, and the eye-lobes are about half these lengths. In 

 Bohemian specimens the proportion is more nearly a third. The 

 front of the glabella is always truncately rounded, and has about 

 twelve lines of discontinuous hair-like rugosities (figs. 10 & 11) 

 near the anterior border. Similar rugosities are seen on some of the 



