GRAPTOLITES OF NEW YORK, PART 2 i~C 



slightly convex, apertural margin gently concave, and normal to axis of 

 theca. Without apertural appendages. 



Position and locality. In the Normanskill shale at Glenmont, Albany 

 co., N. Y. On some slabs associated with D i c e 1 1 o g r. gurleyi, on 

 others with Dicranogr. nicholsoni var. diapason. 



Remarks. This species is based mainly on two specimens (cotypes), 

 one of which exhibits splendidly the basal parts, but has the frond much 

 broken and stripped, while the other lacks the base, but appears to retain 

 the whole frond. The thecae and dimensions of the branches are the same 

 in both. 



While the frond occupies in one specimen only a section of a circle and 

 has the appearance of a flabellate form, it is more probable that originally 

 it was infundibuliform, for the branches are densely crowded along the two 

 radial sides and lie in the middle part distinctly in two layers which have 

 somewhat different directions. 



In its general habitus the form reminds one most of Callograptus 

 salteri from the Beekmantown beds. It has received its name from the 

 peculiarly lobate form of the disk which strongly recalls the liverwort. 



ptioqraptus gen. nov. 



TLtym. ption, fan; grapjio, I write 



This generic term is proposed for a species which in its subparallel 

 branches connected by transverse dissepiments resembles a Dictyonema but 

 differs mainly in having a flabellate rhabdosome instead of the cyathiform 

 or infundibuliform one of Dictyonema s. sir. The genotype — and thus 

 far single species — P. percorrugatus, is distinguished besides from 

 most species of Dictyonema in the marked alternating emptying of the 

 thecae on opposite sides of the branches and the resulting alternate 

 arrangement of the apertural processes. Similar apertural processes have 

 been described by Wiman of D . p e 1 1 a t u m and D . cavernosum 

 and by the writer of D. furciferum, but in these they are only found 

 on one side of the branches and they do not unite with those of the 

 opposite branches forming new processes which grow parallel to the 



