GRAPTOLITES OF NEW YORK, PART 2 



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very rarely observable. The first theca originates near the middle of 

 the sicula and the second theca close to the budding point of the first, 

 both thecae growing in opposite directions. They are furnished with 

 apertural mucros. The thecae are long and slender; their length is five to 

 six times as great as their width ; those of the main stipes number only six 

 to seven in 10 mm on account of the small overlap of the thecae (one fifth of 

 length); those of the secondary branches number seven to nine in the same 

 space, with an overlap of nearly one third their length and an inclination of 



Fig. 192-95 Nemagraptus gracilis (Hall). Fig. 192 Copy of one of Hall's original figures. Fig. 193 

 Copy of Emmons's figure of lt Nemagrapsus elegans." Fig. 104, 195 Enlargements (x 5) Df portions of a speci- 

 men from the Normanskill 



1 5 in the secondary branches. The outer margins are straight ; the aperture 

 is slightly introverted. A neraa has not been observed. 



Position and localities. Hall described the species from the shales at 

 the Normanskill (Kenwood). It is one of ""he most typical, though not of 

 the most common forms of this horizon in New York State. We have 

 before us series of fine specimens from Kenwood, the original locality, 

 Glenmont, Mt Moreno near Hudson, Stockport and fragmentary material 

 from other localities in the slate belt. It has been recorded from the same 

 beds in New Jersey [Weller], Maine [Dodge], Canada [Lapworth and Ami] 



