GRAPTOLITES OF NEW YORK. PAUT 1 621 



not to have been fruitful of further forms, like the main stem 

 of the Clonograptus forms, and the small branch became soon extinct. 

 There have been found two more forms in the Deep kill beds with the 

 same rigid Goniograptus structure, but thecae of different dimensions-. These 

 forms show that there exists a whole group presenting these characters of 

 structure different from those of Clonograptus and recpiiring recognition. 

 But their different thecae leave also little doubt that the genus is polyphy- 

 letic [ch.lO, p.561]. The name then still would designate a definite phyletic 

 stage or tendency of development which it seems became manifest only in the 

 Pacific-American basin [p.503]. 



Goniograptus thureaui McCoy 



Plate 6, figures 1-15 



Didymograptiis (Goniograptus) thureaui McCoy. Ann. and Mag. Nat. 



Hist, ser.4. 1876. 18:128-130 

 Graptolites (Didymograptus) thureaui McCoy. Geol. Sur. Victoria. 



Prodr. Pal. Yietoria, decade 5. 1877. p.39, 40 

 Goniograptus thureaui var. selwyni Ami. Can. Record Sci. 1889. 



3:422-28, p.502, 503, fig.l, 2 

 Goniograptus thureaui Ami. Geo!. Sur. Can. Eep't. ser. 2. 1889. v.3, pt2, 



p.ll6k 

 Dichograptus (Clonograptus, Goniograptus) thureaui Freeh. 



Lethaea palaeozoica, Bd 1, Lief. 3. 1897. p.600, fig.165 

 Goniograptus thureaui Ruedemann. N. Y. State Paleontol. An. Rep't. 1 902. 



p.556, 565, 576-92 



Among the many pretty patterns of graptolite structure occurring in 

 the zones Avith Tetragraptus and Didymograptus bifid us 

 undoubtedly the most beautiful is G . thureaui McCoy. Our interest 

 in this form is enhanced by its peculiar distribution and the fact that it 

 has left a complete record of its ontogeny [1902, p.576]. 



The form ^vas first made known by McCoy from the black and red 

 auriferous slates of the Bendigo gold field, at Sandhurst, Victoria, 

 Australia, and the new genus Goniograptus based on the same. In 

 1889 Dr Ami announced the discoveiy of this remarkable graptolite in the 



