IO NEW YORK STATE MUSEUM 



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Eichwald. It shows distinctly the impressions of what Rauff terms 

 the proximal arms of the meromes or skeletal elements which are 

 directed toward the apex. . 



Plumalina plumaria Hall 



The State Museum contains a large collection of splendid material 

 of Plumalina plumaria Hall from the Ithaca beds at 

 Ithaca. This fossil is with its long pinnate branches not only one 

 of the most striking forms of the Portage fauna, but also one of 

 the most puzzling of that remarkable association, which has afforded 

 to the paleontologist so many peculiar and interesting organisms. 



Plumalina plumaria was first described by Hall as a 

 graptolite (Can. Nat. and Geol., 3:175. 1858). Dawson (Quart- 

 erly Jour. Geol. Soc, 18:314. 1862) subsequently described this 

 New York fossil as a plant, referring it to Lycopodites 

 v a n u x e m i , and P . plumaria is still cited among the plants 

 in Miller's " North American Geology and Palaeontology," 1889, 

 page 134. Hall in his " Graptolites of the Quebec Group " (Figures 

 and Descriptions of Canadian Organic Remains, decade II, 1865), 

 his last and most complete work on graptolites, does not cite Plum- 

 alina any more, probably in consequence of Sir William's publica- 

 tion. In 1878, however, in the 30th Annual Report of the New 

 York State Museum of Natural History, page 255, plate 4, the same 

 author returned to the investigation of that fossil, giving a plate of 

 excellent figures. He mentions that since the first description of 

 t the genotype other forms have come under his observation, until 

 at least six species are known. Of these he says : 



In all the species observed, the usual form is that of a simple 

 frond, or hydrocaulus, with narrow, linear pinnulae diverging from 

 each side, essentially in the same plane, and more or less ascending. 

 Rare examples are bifurcating or otherwise branching, . and the 

 specimen shown on plate 4, figure 1, is the most remarkable example 

 of this kind observed. Although usually occurring singly, it is 

 evident from the figure given in the Report of the Fourth Geological 

 District, as well as from other specimens known, that they may 

 . grow in tufts. No evidence of fertile cells or hydrothecae has 

 been seen, and no distinct serration of the pinnulae can be made 

 out in the specimens examined. From certain appearances upon 

 some specimens, I infer that the pinnulae were cylindrical, and 

 probably tubular, their present appearance being due to extreme 

 compression. 



From the general aspect of these fossils, they appear to be 



