16 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 17, 



G. PRiSTis, Hisinger?, Plate I. fig. 6. 

 Syn. G. pristis, Portlock, Geol. Rep. pi. 19. figs. 10 & 11. 



Our specimen is the base of the stem, and has not yet the serra- 

 tures distinctly marked ; this is also the case with some of Portlock' s 

 specimens. 



Loc. Red slate. Loch Ryan. 



G. PRISTIS var. foliaceus, Portlock. 

 Syn. G. pristis, var. foliaceus, Portlock, Geol. Rep. pi. 19. fig. 9 a. 

 Loc. Black slate, Wigtownshire. 



G. RAMosus, Hall, Plate I. fig. 7. 

 Syn. G. ramosiis. Hall, Paleont. New York, pi. 73. fig. 3. 



Axis cleft, the branches divergent and bearing polype-cells on the 

 outer edge only. I should be disposed to refer this to G. pristis, for 

 the unbranched portion is much like it, and such a monstrosity does 

 not seem unlikely in so thin a plate, with a double series of cells. We 

 have two specimens affected in this way, and another species men- 

 tioned afterwards. 



Loc. Red slate. Loch Ryan. 



G. T^NiA, Sowerby and Salter, n. sp. Plate I. fig. 8. 



Linear, very long ; axis lateral, slightly thickened ; a thickened rib 

 runs along the opposite edge, and the teeth or polype-cells project 

 very little beyond it ; they are appressed along the edge, probably on 

 one of the flat sides, the teeth scarcely projecting ; two cells together 

 longer than the stem is broad ; stem reticulate, the axis crossed by 

 sharp close striae ; a short rib descends obliquely from the top of each 

 cell to the middle of the stem opposite the next cell. 



The last-mentioned ridge may mark the inner boundary of the 

 polype-cell, which projects so little in this pretty species, and is 

 therefore very likely seated upon the flat side. Our specimen, if this 

 be the case, shows the barren side : the longitudinal thickening along 

 the polype-bearing edge is very curious ; it may be occasioned by the 

 superior strength of the cells resisting pressure. 



Loc. Black slate, Wigtownshire. 



G. TENUIS, Portlock? Plate I. fig. 9 — a, 



A specimen supposed to belong to this species, 6 inches long, is 

 bent and broken ; the entire part, 4 inches long, is bent into a 

 strong curve ; and upon the belly of the curve are hooked eighteen 

 specimens of a small two-branched Graptolite, with teeth outside ; 

 they were evidently caught on each other while drifting. At first 

 sight these small Graptolites appear as if they were straight ones 

 caught upon the long stem, and folded or bent double by the current, 

 but a closer examination shows they are forked at the same or nearly 

 the same angle of 50°, and one or two lying by themselves on the same 

 slab are of the same form ; those which do show the teeth distinctly 

 have them on the outer edges. The species appears to be the same 

 as that described by Hall as G. sextans. 



