190 THE VOYAGE OF H.M.S. CHALLENGER. 



were all obtained in depths of over 2000 fathoms. In this genus the corallum is 

 smaller and more delicate than in any other Schizopathina?. In the case of Bathy- 

 pathes patula, which was probably obtained at four stations, it is important to note 

 that typical specimens were obtained only in 2050 and 2900 fathoms in the deep water 

 west of Japan. Two specimens, which appear to be immature forms, were obtained in 

 1428 fathoms off the Banda Islands, whilst the var. plenispina occurs in still shallower 

 water, off the Admiralty Islands in 1070 fathoms. This form has a proportionately 

 stronger stem than the type, and the spines are both larger and much more numerous. 

 The species has evidently a very wide bathymetrical range, practically from 1000 to 

 3000 fathoms. The genera Cladopathes and Taxipathes differ in several important 

 respects from other Schizopathinee, and in the form of corallum approach closely that 

 of certain Antipathinge. In both genera the corallum is strong and much branched, 

 and the dimorphic zooids, in Cladopathes at any rate, are not so completely separated 

 as in other forms. Cladopathes plumosa has been obtained in 310 fathoms, Taxi- 

 pathes recta in 420 fathoms. It would be almost impossible to decide that either 

 species belonged to the Schizopathinas from an examination of the skeletal characters 

 alone. It thus appears that in the Schizopathinas a considerable increase in depth is 

 associated with a simplification in the type of corallum and a greater isolation of the 

 dimorphic zooids. 



A further point which should be mentioned is, that only two species of Antipatharia 

 are at present known from depths between 500 and 1000 fathoms, although seven 

 species have been obtained at greater depths. It is a curious fact that none of the 

 Challenger species have been dredged within those limits. 



