GRAPTOLITES OF ^EW YORK. TART 1 761 



18 Fragment of mature rhabdosome showing the length attained by the 



branches 



19 Principal stem with branches, enlarged to show the composition of the 



stem internodes of one theca each. x2 



20 Restoration of a mature rhabdosome in undistorted condition 



Graptolite bed 3 of the Deep kill section 



