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VIII. — Report on the Pennatulida dredged by H.M.S. " Triton." By A. Milnes 

 Marshall, M.D., D.Sc, M.A., Fellow of St John's College, Cambridge, 

 Beyer Professor of Zoology in Owens College. (Plates XXI. to XXV.) 



(Read 16th July 1883.) 



Introduction. 



The Pennatulida obtained by H.M.S. "Triton," and placed in my hands for 

 description, are of six genera only, each genus being represented by a single 

 species. The interest of the collection is, however, far from commensurate 

 with its size, for of the six species two are altogether new to science, a third 

 has hitherto been met with only off the Norwegian coast, while concerning the 

 remainder, which are well known species, the "Triton" specimens have furnished 

 important additions to our knowledge, either of their anatomy or distribution. 



In arranging the species I have followed the system of classification pro- 

 posed by Kolliker in his " Report on the Pennatulida dredged by H.M.S. 

 'Challenger.'""" This scheme, though representing the latest results of our 

 greatest authority on the group, cannot be considered altogether satisfactory, 

 inasmuch as but very little attempt is made to express the mutual relations of 

 the several groups, and highly specialised forms are mixed up with more primitive 

 ones in a very confusing manner. I have, however, thought it better to adopt 

 it here rather than attempt to frame a new scheme on inadequate material. 



The following outline of Kolliker's classification shows the position 

 occupied by the genera with which we are concerned : — 



Order PENNATULIDA. 



Section I. Pennatule^e : polyps fused together to form leaves. 

 Sub-section 1. Penni/ormes: leaves well developed. 

 Family 1. Pteroeidiclae. 



Family 2. Pennatulidse. 



Genus Pennatula. 

 Sub-section 2. Virgulariece : leaves small. 

 Family 1. Virgularidse. 



Genus Virgularia. 

 Family 2. Stylatulidse. 



Genus Dubenia. 



* Zool Chall. Exp., part ii. pp. 33-35, 1880. 

 VOL. XXXII. PART I. X 



