NOTE ON SOME OBSCURE ORGANISMS IN THE ROOFING SLATES 

 OF WASHINGTON COUNTY, NEW YORK. 



By James Hall. 



For some years there has been in the State Museum several speci- 

 mens of roofing slate from Middle Granville, Washington county, N. 

 Y., showing what have been considered as obscure plant or graptolitic 

 markings. They were presented by Kev. J. E. Baker, of Rochester, 

 and were placed upon exhibition among the fossils of the Quebec 

 group. Two of the specimens are of such remarkable form, and since 

 organic remains are so unusual in the slates of this locality, it seems 

 desirable to make some published record of them. 



The smallest specimen measures 70™"' across, and shows six ovate 

 peripheral expansions, with short stalks, radiating from a small cen- 

 tral disc. The larger specimen has a diameter of nearly 130™™ and 

 diflfers from the preceding not only in size, but in the length of the 

 foot stalks of the leaf-like expansions, which are from 10 to 20™™ long. 



The peripheral expansions or bodies, preserve more carbonaceous 

 matter than the stalks or the central disc, and would appear to indi- 

 cate that they were of firmer (possibly chitinous) texture and con- 

 tained more organic matter. 



The distal ends of the expansions show a dark spot surrounded by 

 light and dark concentric bands, such as Avould be preserved if the 

 body had been a bulb open at the end, or contained a large vesicle. 



It is difficult to determine the true biological position of these 

 obscure specimens. Tiiey difier in their mode of growth from the 

 compound fronds of graptolites, such as Graptolithus, Eetiograptus, 

 Loganograptus or Phyllograptus, in having six rays to the frond, 

 while in those genera the multiplication of the branches is by regular 

 dichotomy or is four rayed as in Phyllograptus. 



Associated with these organisms are fragments of other organisms 

 which have all the appearance of undoubted plant remains (described 

 as Facoides flexuosa, by Emmons) and from the absence of character- 

 istic graptolites in the shales, it would seem to Avarrant the conclusion 

 that these radiate specimens are not of graptolitic origin, but are refer- 

 able to the speuges or possibly the marine algae. 



The name Dactyloidites hulbosus is proposed for these fosails. See 

 plate 11, figs. 1, 2. 



