I32 NEW YORK STATE MUSEUM 



smooth surface; branches mostly simple from the base 13-14 cm 

 long, 



Found in the cement beds of the Waterlime, Buffalo (N. Y.) 

 (Grote & Pitt) 



Genus arthrophycus Hall 



[Ety. : apOpoy, a joint; <pd/.o?, a seaweed] 



(1852. Pal. N. Y. 2:4) 



Stems simple or dividing at the beginning and remaining simple 

 thereafter ; rounded or subangular, flexuous, transversely marked by 

 ridges or articulations. 



Arthrophycus harlani (Conrad) (Plate 16) (1852. Pal. N. ,Y. 

 2:5, pi. 1 and 2) 



Distinguishing characters. Strong, rounded articulated stems, di- 

 viding near the base into numerous elongated branches; simple, 

 flexible, articulated branches which diminish in size very gradually. 



Found on the under side of certain sandstone beds in the upper 

 part of the Medina in the Niagara section. 



Genus nematophycus Carruthers 



[Ety.: vrjtia, thread; <pu-/.o$ , seaweed] 



(1872. Month, micro, jour.) 



Considered a gigantic alga, with cylindric branching stems, and a 

 peculiar structure which led Dawson to refer it to the Coniferae 

 under the name Prototaxites. What resemble concentric 

 rings of growth and medullary rays appear; cells irregular, cylindric, 

 thick walled. The specimens are generally silicified. 



Nematophycus crassus (Penhallow) (1896. Nematophyton 

 crassum Penhallow. Can. record of science. July 1896, 7:151-56, 

 pi. 2) 



Distinguishing characters. Section showing numerous irregular 

 round or oval medullary spots ; large cells in groups, thick walled. 



The specimen is the basal portion of a stock showing root pro- 

 cesses; length 56 cm, diameter at upper end 7.5 cm, widening 

 toward base to 16.5 cm. 



Found in the Manlius limestone of North Buffalo. (F. K. Mixer) 



