T 



OCTOCORALS 



PART I. PENNATULARIANS 

 By Hjalmar Broch 



(The Zoological Laboratory, Oslo-Blindern, Norway) 



(Plates XI and XII, text-figures 1-5) 



INTRODUCTION 



HE Discovery collections of pennatularians are not very extensive. This is not especially sur- 

 prising, because the structure of the species living at greater depths and their mode of life on 

 the muddy bottom enable them to escape most collecting gear, a fact emphasized on an earlier 

 occasion (Broch 1957). 



The collections include the following species : 



Cavernularia elegans (Herklots) Umbellula lindahli Kolliker 



Veretillum cynomorium (Pallas) Pennatula rubra Ellis 



Actinoptilum molle Kiikenthal Pteroeides griseum (Bohadsch) 

 Renilla miilleri Kolliker 



With the exception of Umbellula lindahli, all the species belong to the coastal shelf waters and 

 mostly to shallow depths above some 100 m. Renilla mulleri is an American species, whereas the others 

 belong to the Atlanto-African fauna, Actinoptilum molle being known only from the coastal waters of 



South Africa. 



The genus Umbellula was represented by comparatively rich material from Antarctic waters, and 

 I therefore seized the opportunity to make a critical study of the much disputed species of this genus. 

 An introduction to such a revision has recently been published in the report on the pennatularians 

 of the Swedish Deep-Sea Expedition (Broch 1957). A broader survey on the other hand, necessi- 

 tated both material from different areas as well as a re-examination of types described from earlier 

 expeditions: especially those from the 'Challenger' Expedition. This work was made possible by a 

 grant from the National Institute of Oceanography; I am greatly indebted to Dr N. A. Mackmtosh 

 who arranged this for me, thus allowing me to extend the scope of my study beyond the strict limits 

 of the Discovery collections. 



Prior to 1939, Mrs L. M. I. MacFadyen (nee Dean) worked on these collections at the British 

 Museum, but for various reasons she was unable to write an account. After the war the whole 

 collectiori was sent to me for report, together with her valuable notes. By agreement with Mrs 

 MacFadyen I have made full use of these notes as indicated in the text. 



My work at the British Museum (Natural History) was facilitated in every way by Miss Helene 

 E Bargmann of the staff of the National Institute of Oceanography, and by Dr W. J. Rees and 

 Mr Ernest White of the Museum. I wish to express my gratitude for their never-ceasmg aid and 

 counsel on all occasions. 



