Grapiolites. 369 



name, and I gladly find another in the name of the original 

 describer of the species. Fig. 3, c is the proximal end of the 

 polypary. Fig. 7> G. Halli, Barr. Fig. 8, a and b are two 

 perfect specimens of a beantifnl small species, which at first 

 I referred to G. millepeda, M'Coy, but that species is certainly 

 the proximal end of G. Bechi, and this differs from it in having" 

 a very broad common base, from which the hydrothecce rise. 

 I have dedicated this species to my late friend, J. Morison 

 Clingan, M.A., who was my frequent companion in rambles 

 among the Moffat Hills. G. Olingani could not have been 

 part of a compound organism, as Hall supposes, but is evidently 

 complete in itself. Fig. 3, b represents a specimen of another 

 species, in which both extremities are perfect ; and, though I 

 have never seen large specimens showing both extremities, 

 yet fragments of the ends are not unfrequent, and these con- 

 clusively show that the complete organism corresponded in 

 structure with the small and more frequently perfect G. 

 Clingani. 67. convolutus, His., is represented at Fig. 15. 



3. Gyrtograpsus, Car. Polypary compound; growing in one 

 direction from the primary point. One species only is known 

 from the Wenlock rocks. 



4. Didymograpsus, M'Coy. Polypary compound ; growing 

 bilaterally, and consisting of two simple or double branches. 

 In this genus I include Salter's Tetragrapsus, some species of 

 which would, perhaps, better be joined to DicJwgrapsus. 

 Eleven species of this have been observed, all from the 

 Llandeilo beds, except one, which is found in the Caradoc 

 series. Fig. 12 is D. Miirchisonii, Beck. sp. ; Fig. 14, 

 D. crucialis, Salt. sp. ; and Fig. 16 is an undescribed species 

 from the Moffat shales, for which I propose the name 

 D. elegans. A young specimen is figured at 16, b, and c, 

 showing the (C radicle," which subsequently disappears, and the 

 three processes on the convex side, which are always present in 

 this, as in some other species of the genus. 



5. Dichograpsus, Salt. Polypary compound ; growing 

 bilaterally, and branching r< gularly ; the non-celluliferous bases 

 of the branches invested with a corneous disc. Several 

 species of this genus have been found in Canada, but hitherto 

 only two have been detected in the Llandeilo beds of this 

 country, of which J), aranea, Salt., Fig. 11, is one. 



6. Clodograpsus, Car. Polypary compound ; growing bi- 

 laterally from the primary point, irregularly, and repeatedly 

 branching and rebranching, and without a central disc. Two 

 species of this genus occur in Britain, both in the Llandeilo 

 beds, one of which, G. linearis, Car., is figured Fig. 17. It is 

 a very slender species, and the drawing represents it as some- 

 what too broad. 



VOL. xi. — no. v. B B 



