538 NEW YORK STATE MUSEUM 



PLATE 25 



Diplograptus foliaceus var. acutus Lapworth 



Page 349 



1 Portion of slab with smaller variety of this form 



2 Rhabsodome possessing broad straplike nemacaulus 



Normanskill shale, Glenmont, N. Y. 



Diplograptus foliaceus var. alabamensis nov, 



Page 352 



3 Rhabdosome, showing the common features of the form ( cotype) 



Trenton shaly limestone, Pratt's Ferry, Bibb co.. Ala. 



Diplograptus foliaceus mut. vespertinus nov. 



Page 352 



4 Relatively large rhabdosome (cotype) 1 



Utica shale, Van Schaick island, Cohoes, X. Y. 



5 Group of rhabdosomes of the common size (cotypes) 



Utica shale, Amsterdam, N. Y. 

 18 A rhabdosome of the group figured by Hall [v. i, pi. -J2, fig. ia] from 

 the Lorraine shale at Turin, Lewis co., X, Y. and apparently 

 beloncfincr here. 



Diplograptus crassitestus sp. nov. 



Page 354 



6 Typical rhabdosome (cotype) 



Sylvan shale, Arbuckle mountain:;, Indian Territory 



Diplograptus foliaceus McCoy 



Page 361 



7-9 Three rhabdosomes of " Graptolithus secalinus," showing the differ- 

 ent forms resulting according- to the angle between the direction 

 of the orogenic stress (direction of pointer) and the axis 

 of the rhabdosome 

 'An enlargement of a portion of this rhabdosome is shown in text fig. 293 (errone- 

 ously brought under the var. a c u ( u s). 



