GRAPTOLITES OF NEW YORK, t'ABT I 677 



Like Neumayr and Wiman, Freeh also holds that it can not be expected 

 that the graptolites will show any close relationship to any living class of 

 forms ; but urges that one should rather expect to find the terras Hydi-ozoa 

 and Anthozoa, based on living foi-ms, unapplicable to the paleozoic tyjies; 

 and, on noting an analogy between the embryonal development of the 

 Axonolipa and that of the tabulate corals, suggests that these together 

 with the Stromatoporidae occupied the place of the present Hydrozoa. It 

 is added, however, that whoever desires to force the graptolites into the pres- 

 ent zoologic system, must place them near the H3'drozoa. 



We fully agree with the last named author that it would be mislead- 

 ing to attempt to unite the graptolites with any class of living forms, but 

 at the same time wish to emphasize the necessity of using a group of 

 similar forms as means of reconstructing, if only by analogies, the picture 

 of the organism and thereby gaining new working hypotheses to stimulate 

 investigation. Thus Freeh discusses most fully the relations and differences 

 between the graptolites and the Plumularidae, and that directly after the 

 statement that the graptolites can not be expected to be fitted into a class of 

 living forms. 



Moreover, even if an extinct group can not directly be placed within 

 the confines of a class of living forms, it must naturally be more nearly related 

 to one group of organisms than to all others that exist at present; and 

 there is certainly much gained for the understanding and elucidation of the 

 extinct forms, if this group is found. In this sense the present writer 

 adduced the Siphonophora for comparison, when desciibing the pneumatocyst 

 of Diplograptus ; and later on emphasized the close similarity between the 

 generative cysts observed in Diplograptus and the "gonangia" of the 

 sertularians ; and for the same reason the Hydrozoa have been used through- 

 out this treatise as a standard by comparison with which an understanding of 

 the graptolites is sought. 



