2 24 NEW Y0RK STATE MUSEUM 



writer some years ago in the Utica shale of the Mohawk Valley, X. Y., also 

 in but one specimen. This is here described as C , g e m m a t u s. 



Although the rhabdosome of C . novellus has superficially the 

 appearance of branching tubes and except in its carbonaceous substance 

 appears to have little in common with the graptolites, closer inspection 

 leaves no doubt of the composition of these tubes of cells resembling thecae. 

 We have here [pi. 11, fig. 5] reproduced some of the best preserved por- 

 tions of the type specimen to bring out their composition of small curved 

 cells and the thecal character of the numerous short 1 tranches. Hall had 

 fully recognized this structure, when he stated that "the branches and 

 branchlets are marked by numerous cellules which are usually indicated by 

 the appearance of abrupt expansion and contraction of the branches." The 

 original drawings, however, fail entirely to bring out this feature. The 

 Devonic specimen, though not so well preserved, shows also distinctly this 

 composition and Clarke describes it as consisting "of curved, commalike 

 bottle-shaped cells or branch segments, which bud in such a fashion from 

 the preceding that the branches become slightly zigzag-shaped." 



The Utica shale specimen is also fragmentary but more distinct in the 

 parts preserved than the other types. It shows a common canal formed by 

 the bases of the cells or thecae and abruptly outward bending cell bodies. 



The attached, creeping mode of existence of two of the species and the 

 peculiar form of the cells are so different from what we are accustomed to 

 see in graptolites that one shrinks from definitely assigning the genus to that 

 class. The question of the graptolitic nature of these tonus was mooted 

 in this office when Dr Clarke investigated the Devonic species and the pos- 

 sibility of its bryozoan nature considered. To attain clearness on the latter 

 point the specimens were sent to Dr Ulrich who however has been unable 

 to recognize them as bryozoans. The)- thus fall bark into their old associa- 

 tion and it becomes necessary to attempt to reconcile their anomalies with 

 the normal graptolite structure. 



The creeping mode while the prevailing one is apparently not their 

 only one, for Hall states that C . novellus also occurs free and the type 



