240 



Dr. H. A. Nicholson on the Occurrence 



The cellules are from three to six on a pinnule ; when well 

 exhibited, they are angular, projecting, and closely resem- 

 bling the cellules in some forms of Graptolites Nilssom, 

 Barr. The test is corneous, and there are no traces of any 

 solid axis. 



The entire frond is not known to me ; but I have seen frag- 

 ments of nearly two inches in length. Wliether this species 

 is absolutely distinct from that of the Quebec group, termed 

 by Hall P. plumosuSy it is difficult to say, in the absence of the 

 cellules of the latter. It is, however, highly improbable that 

 the species should have survived tlu'ough a period of time so 

 vast as this would imply. Our species, too, is of a much more 

 slender and graceful habit than is the case with either of the 

 American species, whilst the branching is more diffuse and the 

 pinnula3 are shorter. 



Loc. In a greenish-grey mudstone, of Lower Ludlow age, 

 from Bow Bridge, near Ludlow. 



Ptilograpsus anglicus, spec. nov. 



1. A small portion of a frond, natural size. 



2. A single branchlet, enlarged. 



3. A single pinnule, enlarged, to show the cellules, 



4. Branched Graptolite (Ptilograpsus?) from the Lower Ludlow rocks 



of Bow Bridge, near Ludlow, nat. size. 

 6. A portion of the same, enlarged, showing pinnulse and cellules (?). 



In the same bed with Ptilograpsus anglicus there occurs a 

 branching fossil, in the same state of preservation as the former, 

 and almost certainly Graptolitic, though I have failed to de- 

 tect cellules except in one instance, and then not with cer- 

 tainty. I possess, however, but a single specimen, which I 



