GRAPTOLITBS OF NEW YORK, PART 1 627 



and all other multiramous dichograptids known to the writer, in having 

 these points close to the apical end of the long sicula. It has been noted 

 in the chapter on the phylogeny of the dichograptids [p.561] that this 

 is one of a number of characters which indicate a connection of this 

 species with a separate phylogenetic series of forms, ending in the coeno- 

 graptids. A form presumably derived from this species, described here as 

 Sigmagraptus praecursor, 

 differs only in the formation of 



+.A;c-r> inatpfirl r>f fnnr i-irinpiiml afpine • Fiir. 42 GonioBraptus perflexllis gp. nov. 



IWO insieau OI lOUr principal SiemS , Enlargement of portion of branch of the epecfmen 

 , , - , , (• 1 1 reproduced on plate 7, flgrure 7. Deep kill. x7 



and the development ot the lower 



left and upper right principal stems of G, perflexilis into nondividing 



branches would directly lead to that type. 



A peculiar feature of the largest specimen figured is a large, chitinous 

 body, suggesting a collapsed bag, adhering to the initial part of the rhabdo- 

 some [pi. 7, fig.9]. Whether this distinctly outlined structureless body is the 

 remains jf a central disk or of an unknown parasitic growth, it is impossible 

 to decide by means of a single specimen. A central disk of the alate char- 

 acter observed in G.thureaui has not come to observation in this species. 



The specimen obtained from the beds at Mt Moreno [pl.6, fig.l6], if 

 indeed belonging to this species, presents an extreme development of the 

 flexible or flaccid character of the branches of the species. It has there- 

 fore been distinguished as mutatio flaccida. The apertures of its hairlike 

 thecae are 2 . 5 mm apart and the thecae appear to be in contact not more 

 than one fourth of their length. 



Goniograptus geometricus sp. nov. 



Plate 7, flgures 10-20 



Cf. Thamnograptus anna Hall. Geol. Sur. Can. Canadian Organic Eemains, 



decade 2. 1865. p.l41, pl.21, fig.9 

 Goniograptus sp. nov. Ruedemann. N. Y. State Paleontol. An. Eep't. 1902. 



p. 566 



A surface of graptolite bed 3, belonging to the horizon with Di d ymo- 

 g r a p t u s b i f i d u s , is entirely covered with the rhabdosomes of an 



