GRAPTOLITES OF NEW YORK, PART 2 285 



and from Stockport, where it is found with Dicellogr. sextans and 

 C 1 a t h r o g r. g e i n i t z i a n u s. 



In Great Britain it is "a comparatively common form in the Glenkiln 

 shales of S. Scotland" and it also occurs in N. Ireland. 



Nemagraptus gracilis var. crassicaulis Gurley 



Plate 17, figure 13 



Stephanograptus crassicaulis Gurley. Jour. Geol. 1896. 4:68 

 The original description of this species is : 



Specimen resembling one half of S. gracilis but with a much 

 thicker curved main stem and branches, the former measuring from 0.50 to 

 0.75 mm in thickness, the latter in the distal portions attaining a width of 

 1 mm. The branches are given off from the main stem at first at a right 

 anode, but with each succeeding branch the divergence becomes less. The 

 thecae on the distal portion of the branches measure 20 in 25 mm. 



Horizon and locality. Lower Diccllograpsus zone, Stockport, N. Y. 



This species differs from all others of the genus in its very stout poly- 

 pary. Though only one half of the polypary has been seen, the generic 

 reference seems hardly open to doubt so much does the habit of the species 

 resemble that of S . gracilis. 



Since Gurley has not published any figures, we insert here two [text 

 fig. 198], which accompanied his manuscript and were approved by him. 

 These are to be considered as the type figures of the variety. We also add 

 two further figures of the same material to illus- 

 trate features not brought out by the original 

 drawings. 



We have not found any other specimens 

 of this remarkably robust form, but would sup- 

 plement the original description by the follow- 199 



Fig. 198, 199 Nemagraptus gracilis 



ing data taken from the type and a cotype (the var crassicaulis Guriey. Fig. 198 Gur- 



fc> J i y 1 \ leys original drawings. fig. 199 tnlarge- 



1 1 \ ""PI. * 1 A irent (x I) of portion of one of Gurley's types 



Only tWO Specimens known): I lie SICUla and (Originals in National Museum) 



primary thecae are not exposed. The main stem has a width of .6 mm ; 

 the secondary branches one of .4 mm to 1 mm. They are 1 to 2 mm apart 

 at their bases and the thecae of the secondary branches number from six to 

 eight in 10 mm. They overlap about one third their length ; their inclina- 



