188 SUPPLEMENT TO THE 



107. Orthis vel Strophomena ? Kilbuchoensis, Dav. Sil. Sup., PI. XIII, figs. 1 — 2. 



The Geological Survey of Scotland obtained from the Caradoc or Wrae Limestone at 

 Kilbucho, near the church, and two and a quarter miles from Culter in Peebleshire, two 

 magnificent internal casts of an Orthis ?, of which the species is not known to me. 

 These casts are marginally semi-circular, nearly flat, wider than long, with a long straight 

 hinge-line, and show the muscular impressions, central ridge, ovarian spaces, and 

 vascular ramifications in a wonderfully fine state of preservation. 



Not being acquainted with the exterior I cannot describe the species, but have 

 given it a provisional name and added correct drawings of the two specimens in the hope 

 that a search in the locality may be made for more specimens. The figures I have given 

 are enlarged ; one of the specimens measured — length 6, breadth 9 lines ; the other, 

 length 9, breadth 14 lines. The largest drawing shows the real interior drawn from an 

 impression in white gutta-percha taken from the cast. 



108. Orthis Philipi, Dav., Sil. Sup., PI. XI, figs. 13—14. 



Shell small, marginally semi-circular, wider than long, indented in front ; hinge-line 

 straight, dorsal valve moderately convex and divided into two lobes by a deep median 

 sinus. Surface ornamented with numerous thread-like, radiating radii, with wide inter- 

 spaces dotted over with small pits. Ventral valve not known ; length 3|-, breadth 4 lines. 

 In the interior of the dorsal valve the hinge-area is narrow, the valve being divided into 

 two lobes by a wide, roof-shaped ridge. Cardinal process small, situated between two 

 curved brachial processes or plates. Close under the hinge-area and near to the plates 

 are situated the sockets, and on either side of the central ridge are the adductor muscular 

 impressions. 



Ohs. — The ventral valve not having been discovered, it is not possible to give a 

 complete description of this remarkable little species. It was found by Mr. C. Croft, of 

 Manchester, in the Caradoc at Ty-isaf, Lansantfi'raid, in Montgomeryshire. Mr. Croft 

 writes me that he has worked the locality thoroughly, and that he collected not less than 

 two hundred species of different classes and all from one small quarry. I have named 

 the fossil after Robert Philip, Esq., of Minsterley, in Shropshire, who has devoted 

 so much attention to the Llandeilo and Llandovery beds and fossils that occur in his 

 locality. 



