26 Proceedings of the Royal Physical Society. 



ill the accumulation of their fossils. Two entirely separate 

 collections have been made by Mrs Gray. The first was 

 presented to the Hunterian Museum, Glasgow, about 1865 

 or 1866, and the second now forms, without doubt, the most 

 complete series of Silurian fossils ever brought together in 

 Scotland. The second collection has literally been the work 

 of Mrs Gray's own hands, and at a moderate estimate it may 

 be stated that in accomplishing this work from 20,000 to 

 30,000 specimens have been obtained. Several of the most 

 interesting forms of Brachiopoda, described by Mr Davidson, 

 were found by Mrs Gray, such as, Leptcena Youngianct, 

 Triplmsia Graym, Orthis Girvanensis, etc. The results of her 

 first gatherings were communicated in a series of short papers 

 to the Proceedings of the Glasgow Natural Society, by Mr 

 Gray, and Mr John Young, F.G.S. 



The most important of these were, " Note on a New Bra- 

 chiopod Shell, Triplcesia Graya: (Davidson),"* by Mr Young; 

 "Note on Leptmna Youngiana (Davidson)," f by Mr Gray; 

 " Notes on the Genera of Extinct Fossil Shells, Belleroijhon 

 and Porcellia;''X and "Notes on a Series of Fossils from the 

 Silurian Eocks of the Girvan Valley," § by Mr Young. In 

 this paper is announced the discovery of a Eussian Silurian 

 Brachiopod not previously known to occur in Britain. 



The shell previously mentioned, Leptcena Youngiana, is 

 regarded by Mr Davidson as a variety of Leptcena transver- 

 salis (Dalman). For my own part, I should be inclined to 

 regard this as a distinct and separate species, but if a variety 

 of anything it appears to have more affinity with L. tcnui- 

 cincta (M'Coy). 



In 1876 Professor John Young read a short paper before 

 the Glasgow Natural History Society, || on a Silurian fossil 

 from the neighbourhood of Girvan, wdiich he referred to 

 Salter's genus Stenotheca, a free-swimming shell of the class 

 Pteropoda. Professor Young considers that this organism has 

 greater affinity with the Phyllopod Crustacea than with the 

 Pteropoda. He remarks that the shell has the appearance 



* Troc. Glasgow Nat. Hist. Soc, 1868, L, pt. 1, p. 207. 



+ Ibid., 1869, i., pt. 2, p. 229. J Ibid., 1875, ii., pt. 1, p. 16. 



§ Ibid., 1876, ii., pt. 2, p. 166. || rioceedings, 1876, ii., pt. 2, p. 223. 



