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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec. 4, 



but usually the cells are at least equal to the canal in breadth, the 

 latter showing a depressed line extending along its whole length, 

 probably due to compression. The cells have an upward direction, 

 and are very remote from each other, looking merely like notches at 

 intervals along the edge. The upper edges of the cells are straight, 

 and the opening apparently at right angles to the axis. The num- 

 ber of cells in an inch is about twenty, but there is a slight variation 

 in different individuals, those which are curved having more cellules 

 in a given space than those which are straight. It occurs in consi- 

 derable quantities in a small brook which runs from the base of 

 Little Queensberry. Here the shale has a styptic taste, owing to 

 the decomposition of iron pyrites, of which this fossil is composed. 

 Like the generality of pyritous fossils, there is no trace of the exter- 

 nal covering. 



The Grapt. Nilssoni of Barrande has such close resemblance, that 

 we cannot apply a new name. It is quite possible that both this and 

 the Bohemian species may belong to G. tenuis, Portlock, or at least 

 to that figured as such by Hall (Palseont. New York) ; but Port- 

 lock's original specimen is quite indeterminable, and it seems best 

 for the present to retain M. de Barrande' s name. 



5. Graptolites incisus, Harkness. 

 Pl. I. fig. 8. Natural size and magnified. 

 Prionotus Sagittarius, Hisinger, Leth. Suec. t. 35, Supp. f. 6. ? 



Only a small portion of this species has been obtained, and that 

 being only an impression, many of the characters are obscure. It 

 seems to have been of large size and straight, with a well-developed 

 axis. The space between this and the cells is very broad, exceeding 

 that of any other species found in Dumfriesshire. The cells, which 

 are imperfectly shown in the specimen, have an upward direction, 

 and a very oblique position. The mouths of them are distant, but 

 the ends are not distinctly shown ; if a short spine projected from 

 these, it would be difficult to separate this fragment from Hisinger' s 

 species. The number of cells in an inch is about eighteen, and the 

 thickness of the interval between the cells and the dorsal margin is 

 about the twelfth of an inch. 



Locality. Bell Craig Burn near Moffat. 



Besides these, there are two or three more species of this section 

 tolerably abundant, but too imperfect to name. 



Subgenus Diprion, Barrande {Diplogr apsis, M'Coy). 

 1. D. pennatus, Harkness. 

 Pl. I. fig. 9. Natural size and magnified. 

 In this the central column is broad and slightly convex, with a cen- 

 tral axis stronger and more prominent than is usual in the foliaceous 

 Graptolites. Only a portion of the fossil is seen, neither its lower nor 

 upper extremity being shown. As no attenuation is visible, it is pro- 



