Vol. 69.] PALEOZOIC ROCKS OF THE CATTTLEY DISTRICT. 15 



trilobite. A specimen from Backside Beck is a portion of a glabella 

 well preserved in limestone. It shows no sign of glabellar furrows. 

 A single pleuron from this locality differs from the pleura of the 

 Taythes Gill specimen in the direction of the lines, which are 

 parallel to the long axis of the animal. Two species may be 

 indicated. 



Phacops robertsi Reed. — The occurrence of two specimens in 

 the Caradocian beds of Sally Brow marks the arrival of a form 

 peculiarly abundant in the lowest Ashgillian strata. The species 

 is, however, obviously very rare in the Calymene Beds, for much 

 material has been broken up. 



(2) Fossils of the Phacops-robertsi Beds. 



Trinucleus (Tetraspis). — The subgenus is abundant in the 

 Calymene Beds of the Caradocian Series and in the Phacops- 

 robertsi and Staurocephalus divisions of the Ashgillian. I have 

 handed over the material to Mr. E. R. C. Reed, who is at present 

 engaged in studying the genus, and need only remark here that 

 the somewhat imperfect specimens from the Caradocian agree with 

 forms usually referred to Tr. seticomis. This is also the case with 

 those from the Phaoops-robertsi Beds. In these forms the fringe 

 ends near the posterior angle of the head, and a simple spine 

 extends backwards. In the Staurocephalus Beds a form is common 

 which has the fringe prolonged backwards sometimes as far as the 

 pygidium, as in Barrande's Trinucleus bucklancli. 



Remopletjrides (Caphyra) sp. 1. — This form apparently differs 

 from any species hitherto described. 



The anterior tongue is much longer than that of the form figured 

 by Barrande, but agrees fairly with the tongues figured by Lin- 

 narsson 1 and Olin. 2 The ornamentation is quite different from that 

 on Barrande's specimens, and also from that in pi. i, fig. 21 of 

 Linnarsson's paper. Head, body-rings, and tail alike are marked 

 by wavy transverse lines ; similar lines are seen in R. portlocM, 

 figured by Mr. F. R. C. Reed from the Tramore Limestone of Water- 

 ford, 3 and in R. latus Olin 4 ; the other characters of the species here 

 described are different from those of these forms. 



Three pygidia have been found, which, apart from the ornamen- 

 tation, are too imperfect to show the characters. 



This species is extraordinarily abundant in the Phacops-robertsi 

 Beds. 



1 K. Svensk. Vetensk.-Akad. Handl. vol. viii (1869) No. 2, p. 67 & pi. i, 

 figs. 21-22. 



- Meddelande fran Limds Geol. Faltklubb, sect. B (1906) p. 54 & pi. ii, 

 figs. 1-2. 



» Q. J. G. S. vol. lv (1899) p. 746 & pi. xlix, fig. 4. 



4 E. Olin, op. tit. pi. ii, figs. 6, 8, & 9. 



