PALEONTOLOGIC CONTRIBUTIONS 



II 



referable to the family Plumularidae, and their forms and mode 

 of growth may be compared with some species of Plumularia and 

 Aglaophenia. 



We see from this description that Hall in his last paper on the 

 subject referred his species to the Plumularidae (order Campanu- 

 lariae of the Hydrozoa). He also considered the graptolites, like 

 most authors of his time, as related to the Sertularidae and Plumu- 

 laridae. We shall now present evidence indicating that Plumu- 

 1 i n a plumafia is possibly an early representative of the 



Fig. 2, 3 P 1 u m a 1 i n a plumaria Hall. 2 Enlargement (x io) of 

 surface with portion of outer granular rind preserved. 3 Enlargement x 5) 

 of wrinkled axis 



order Alcyonaria ( class Anthozoa) and comparable to such Gor- 

 gonidae as Primnoa with which it also has a striking exterior 

 resemblance. The absence of any distinct thecae or cells forbids 

 placing it with the graptolites or with the sertularians or plumu- 

 larians. On the other hand, w r e have found pinnules (see text fig. 



2) which distinctly show their composition of an inner solid 

 carbonaceous (horny) axis and an outer granular rind. Likewise 

 the stems exhibit an inner, irregularly wrinkled axis (see text fig. 



3) which is surrounded by an exterior rind. Neither the axis 

 nor the rind show any traces of fibrous or other composite structure. 



