Victorian Fossils, Port XIII. 181 



throughout the sihirian {1 Upper Llandovery to Upper Ludlow) 

 in Great Britain, where it has a wider range than any other 

 species of the genus. 



Occurrence. — Silurian (melbournian). Flemington (" Royal 

 Park "). Coll. by the Geol. Survey of Victoria. 



Note on the Shell-Structure of the Above Variety. 



It is remarkable that an ancient brachiopod shell such as 

 this should retain so much of its original structure ; espe- 

 cially since it occurs in so unpromising a matrix. In appear- 

 ance the shells, of which there are at least nine examples in the 

 museum collection, resemble those of the recent corneous 

 Lingiilae, but are darker in colour. They vary from dark 

 brown to almost purple black, and the colouring matter, which 

 appears to be original, is organic, that is to say, carbonaceous. 

 The surface of the shell has a dull sheen, resembling that of 

 polished cow-horn, and under a tolerably high power is seen 

 to be finely punctate. 



As regards colouration, the palaeozoic Linyulae are, as a rule, 

 devoid of colour, an exception being L. si/mondsi, as remarked 

 by Davidson. 1 



The shell-structure of Lingula has been known through the 

 work of Dr. W. B. Carpenter and M. P. Gratiolet. There are 

 certain points in the descriptions by these two authors which 

 are somewhat difficult to reconcile, and some further notes 

 which I hope to publish later upon the structure of the recent 

 and fossil examples may help to clear away these obscurities. 

 It is sufficient to point out here that, whilst Carpenter^ refers 

 to the Liiigulci shells as being " almost entirely composed of 

 laminae of horny matter, which are perforated by minute tubuli, 

 closely resembling those of ivory in size and arrangement, and 

 passing obliquely through the laminae,"' Gratiolet' has described 

 the shell-structure in the living species — L. anatina. Lam. — as 

 composed of several alternating layers of horny and calcareous 



1 Moti. Brit. Sil. Brach. (Pal. Soc), 1866 (1S67), p. 34. "... none of the many 

 fossil species hitherto colleoted throughout the entire sequence of sedimentary deposits, 

 from the Lingula Flags upwards, have sliown the smallest vestige of colour ; unless, 

 perhaps, L. st/movdxi from the VVenlock Shale." 



•2 Rep. Brit. Assoc. (1844), 1845, p. 18, pi. ix., fig. -i-i. 



;» " Etudes anatomiques sur Lingula anatine(L. aaatina, Lam.)." Journ. de Conchyl., 

 vol. viii. (2nd ser., vol. iv.), p. 1860, p. 49. 



