714 NEW YOUIv STATE MUSEUM 



only ill relative size. The form from the quarry beds appears to be 

 transitional between the preceding older mutation, still closely related 

 to P. ilicifolius, and the succeeding typical form in the uppermost 

 horizon. 



Phyllograptus anna Hall 



Plate 15, figures 23-30 



Phyllograptus anna Hall. Canadian Organic Remains, decade 2. 1865, p.l24, 



pl.l6, iig.11-16 

 Phyllograptus anna Lapworth. Roy. Soc. Can. Proc. and Trans. 1886. 



4:168 

 Phyllograptasanna Ami. Geol. Snr. Can. Rep't, ser. 2. 1889. v.3, pt 2, 



p.liek 

 Phyllograptus anna Gurley. Jour. Geol. 1896. 4:294 

 Phyllograptus anna EUes. Quar. Jour. Geol. Soc. 1898. 54:494, fig.l6 

 Phyllograptus anna Elles & Wood. Monogr. Brit. Grapt. Pal. Soc. vol. for 1902. 



p.lOl, pl.l3, fig.6a-f 

 Phyllograptus anna Ruedemann. N. Y. State Paleontol. An. Rep't. 1902. 



p.566, 571 



Description. Rhabdosome small, a single very large specimen attain- 

 ing 13 mm, while ordinarily large specimens measure only 8 and 9 mm in 

 length ; the maximal width of the largest specimen was found to be 5 . 2 mm ; 

 branches broadly semioval, attaining, as a rule, their greatest width near the 

 antisicular end, which often appears truncated. Thecae in contact through- 

 out, very closely arranged, numbering 16 to 20 in 10 mm; those near the 

 sicula being directed outward and curved, the curvature gradually increasing 

 toward the middle where they are strongly curved ; becoming more ascend- 

 ing toward the antisicular end, where they are nearly straight and subparallel 

 to the axis of the rhabdosome. Apertural margins regularly and deeply 

 concave, mucronate extensions of the apertures long, narrow and in the 

 compressed state of nearly uniform width, or sometimes appearing thickened 

 or club-shaped at their distal ends, when more than the lateral margin of 

 the extension is exposed. The character and length of the sicula has not 

 been ascertained. A short stout sicular spine has been noticed in several 

 specimens. 



