DAVIDSON SCOTTISH CARBONIFEEOUS BRACHIOPODA. 



269 



Fig. 16 — 17. Productus iindatus. Two examples, from tlie same locality and col- 

 lection of Mr. Young. 



18. ■ scahriculus, Martin. From tlie Campsie main limestone. The 



interior of the dorsal valve will be found represented in pi. v. 



19. pustidosus, Phillips. North of Glasgow (?) ; collection of the 



Geological Survey. The same thing may be repeated here that we 

 have said under fig. 14. 



20. punctatus, Martin. From near Lesmahago. One part shows 



the spiny investment, of which 20c and d are enlarged illustrations. 



21. . Internal cast of the ventral valve seen from the 



beak, and showing the relative position of the occlusor (A) to the 

 divaricator (R) muscular impressions. 



22. . Interior of the dorsal valve ; collection of Mr. 



Armstrong. 



23. spinidosus, Sow. From the original example in the collection 



of Dr. Fleming. 



24. . From near Lesmahago ; collection of Dr. Slimon. 



25. costatus, var. muricatus, PhilKps. From Cessnock, near Gal- 



ston. This specimen agrees exactly vnth the original example so 

 named in the nmseum of York, and which has been considered a syno- 

 nym of P. costatus. 



26. latissimus, J. Sow. Interior of the ventral valve. From West 



Broadstone, Beith ; in the collection of Mr. Armstrong. 



Plate XV. 



1. Productus giganteus, Martin. Braidwood Gill, Lanarkshire. This 



species attains more than twice the dimensions of the figure. 



2. . Interior of the ventral valve. A, occlusor; R, di- 

 varicator impressions ; L, hollows occupied by the oral arms. 



3. . Interior of the dorsal valve. A, occlusor ; J, car- 

 dinal process ; X, reniform impressions ; Z, prominences correspond- 

 ing with the hollows (L) in the opposite valve. 



4. . Hinge-hne showing the upper surface of the car- 

 dinal process, J. 



5. com. A portion of the external surface magnified to show its 



peculiarly sculptured stri83. Corrie Burn ; collection of Mr. Young. 



6. scahriculus. Interior of the dorsal valve, from two Lanarkshu'e 



specimens : the partially divided mesial ridge and cardinal process 

 are peculiar. From the collections of Mr. J. Armstrong and that of 

 another friend. 



7. ■ Toungmnus, Dav. This figure shows the concentric lines of 



growth, which had not been sufficiently expressed upon the figures 

 already given. 



8. Spiriferina laminosa, M'Coy. Fi-om Lammerton ; in the collection of 



Mr. G. Tate. This is only a cast, the shell being destroyed. 



9. . A fragment of the shell magnified to show the dis- 

 position of the lajBiinse which adorn the surface. 



10. Spirifera hisulcata. A remarkably elongated variety, in the Hunterian 



Museum, Glasgow College. A similar specimen has been found near 

 Lesmahago. 



11. trigonalis (?) . Campsie ; formerly in the collection of Mr. 



A. Cowan, now in that of the Geological Society of Glasgow. I am 

 somewhat uncertain whether this shell, of which many similar ex- 

 amples have been found, is in reality a variety of Sp. trigonalis or of 

 8p. dwplicicosta. 



12 — 13 — 14. Crania quadn'ata^ M'Coy. From Capel Eig and Calderside ; in 

 the collection of Messrs. Thomson and J. Armstrong. 



