620 NEW YORK STATE MUSEUM 



other ; the branches leave the stems with an angle of about 80°. The 

 branches are extremely slender, their maximal width observed being only 

 . 4 mm. The total length attained by the branches and the diameter of 

 the whole rhabdosome are not known. Six branches have been observed 

 on principal stems which were not perfect. The thecae are extremely nar- 

 row, long and tubular, 3 mm long, increasing to 5 mm in the distal stem 



sections ; in the mature branches about 

 six times as long as wide ; in contact 

 more than one half of their length, 

 numbering not more than 6 to 7 in 10 mm, 

 Fig. 40 Goniograptus perfiexiiis sp. nov. ^^d forming au angle of but 5° with the 



Enlargement of a part of the specimen reproduced . p . i_ i_ i rrii i i 



on plate 7. figure 9, to sliow the composition of the aXlS OI tlie brancll. 1 UeV have gentiv 

 steminternodes of thecae and the uliaraoter of the •' o j 



thecae. Deep kiu. x2.5 coucave outcr margins, nearly straight, 



reflexed ap^rtural margins, which form an angle of 60° with the axis of 

 the branch. 



Position and localities. In graptolite bed 2, forming the upper part 

 of the Tetragraptus horizon in the Deep kill section, and rarely also in 

 the next horizon. While younger growth stages were found very frequently, 

 mature colonies are extremely rare in this material. One large fragment 

 referable to this species [pl.6, fig. 16] was obtained from the beds at 



Mt Moreno near 



Hudson which are ^^^^^^^^f^^^^^^^^^^^^^^^^^^'^^P^"* 



transitional from rsg. « Gonlograptus perflexills sp. nov. Enlargement of branch of 



the specimen reproduced on plate 6, figure 17. Deep kill. x5.25 



the horizon with 



Didymograptus bifidus to that Avith Diplograptus 

 dentatus, so that this species ranges fi'om the second to the lower 

 part, at least, of the fourth horizon. 



RemarJcs. This species is at once distinguished from G. thureaui 

 by its extremely slender habit, the narrow branches and longer thecae, the 

 less angular nature of the principal stems, which more approach to a straight 

 line. In the location of the budding and diverging points of the thecae, form- 

 ing the " funicle " it differs markedly from the type species of the genus 



