54 TRILOBITES OF GIRVAN. 



undefined border, length of" axis and width of infra-marginal doublure, there is 

 close agreement. We may also especially note its resemblance to Ph. ecclesiastimis, 

 Olin,^ of the Chasniops Limestone of Sweden, and to Pli. recurvas. Linrs.," of the 

 Trinudeus Shales ; but unfortunately the head-shield and thorax of our Girvan form 

 are unknown. It apparently belongs to that primitive section of the Bal inanitcs 

 group which has been termed by the author Dalmanitina.^ The incipient mucro 

 indicates a nearer approach to the condition in the typical JJdJmanifes than is 

 shown in PJi. vohertai, and thus recalls Ph. viiirroualus, Brong.,"* but the shape of 

 the pleurae and the terminal union of the pleural and interpleural furrows are 

 distinctive features in the latter. 



A specimen of a 2:)ygidium from the Whitehouse Beds of Shalloch Mill, 

 apparently referable to Ph. asleroidens, is remarkable from having the shell 

 preserved on one lateral lobe, and showing on it a peculiar ornamentation of 

 minute crescentic scales, like an Burypterid, with their convexity facing outwards. 



Horizons and Localities. — Starfish Bed, Drummuck Group (U. Bala) : Thraive 

 Glen. Whitehouse Group (M. Bala) : Shalloch Mill. 



1 Olin, " Chasmopsk. o. Triuucleusskif. Skane," Medd. Lunds Geok Fiiltklubb.,' ser. B, no. 1 

 (1906), p. 43, pi. i, fig. G. 



2 Olin, ibid., p. 42, pi. i, figs. 4, 5. 



■^ Eeed, ' Geol. Mag.' [5], vol. ii (1905), p. 224; Wedekiud, ' Zeitsclir. deutsch. geol. GescU.,' 

 vol. Ixiii (1911), pp. 318—336; Eaymoiid iu Zittel-Eastmau's " Palajoutology " (1913), p. 726. 



1 Salter, ' Mou. Brit. Trilob.,' p. 46, pi. iv, figs. 11, 12 ; B. Smith, ' Proc. Roy. Irish Acad.,' vol. 

 xxvi, sect. B, no. 9 (1907), p. 123, pi. viii, figs. 10—13. 



