550 NEW YORK STATE MUSEUM 



PLATE 29 



Genus monograptus Geinitz 

 Monograptus clintonensis (Hall) 



p.. 



je 450 



1 Typical (fragmentary) rhabdosome 



Clinton shale, Genesee gorge, Rochester, N. Y. 



Monograptus priodon (Bronn) mut. chapmanensis nov. 



^1 . Pa S e 454 



2 Typical specimen 



Siluric sandstone, Chapman Plantation, Aroostook co., Me. 



Monograptus beecheri Girty 



Page 455 



3 Two specimens of average size (cotypes) 



New Scotland beds, Indian Ladder, Albany co., N. Y. 



Genus cyrtograptus Carruthers 

 Cyrtograptus ulrichi sp. nov. 



Page 459 



4 Slab with numerous fragmentary specimens (cotypes) 



Bainbridge limestone, Bainbridge, Cape Girardeau co., Mo. 



Genus retiograptus Hall 



Si-e plate 31 



Retiograptus geinitzianus Hall 



Page 463 

 See plate 31, figures 9-17 



5 Perfect rhabdosome, retaining periderm and showing form of thecae 



6 Specimen showing only the system of ledges 



Normanskill shale, Schodack Landing, N. Y. 



