GEOGRAPHICAL DISTIUBUTION. 



ALCYONARIA (exclusive of the Pennatulacea). 



The collection of the Alcyonaria, made during the cruise of the Challenger, has 

 added in some measure to our knowledge of the geographical distribution of the group. 



Of the distribution in space of the various species, the little that was already known 

 has been chiefly through the labours of Verrill, Pourtales, and Studer, for in the important 

 volumes of Esper and Milne-Edwards the localities for the species are often unrecorded, 

 or when given are vague and uncertain. The recent works of Koren and Danielssen have 

 added very considerably to our knowledge of the habitats of the northern forms ; nor 

 must the memoir of Duchassaing and Michelotti, on the species found at the Antilles, be 

 overlooked, though uncertainty must be felt, owing to the absence of some of the types, 

 about the identity of all the species mentioned by these latter writers. 



On a review of the collection made by the Challenger, it seems evident that very 

 many forms remain yet to be discovered in all the oceans, and this not only among 

 shallow-water and reef frequenting species, but also among the species frequenting 

 moderate depths in the sea. Until the record is much more complete, it does not seem 

 advisable to attempt the mapping out of the oceans into " areas of distribution." 



We venture, however, on the attempt to give a brief history of what is known as to 

 the distribution of the species of all the well-established genera, so far as these could be 

 ascertained, even when the species have not been taken during the Challenger's voyage. 



Order I. GORGONACEA. 



Section I. HOLAXONIA. 



Family I. D a s Y r, o R G i d .e. 



Strophogorgia, Perceval Wright. 



Of the four species of this genus, two, Strophogorgia petersi ' and Strophogorgia 

 verrilli, are found in the Pacific Ocean (Japan), while the other two, Strophogorgia 

 challengeri and Strophogorgia fragilis, are inhabitants of the Atlantic Ocean. In both 

 oceans the species occur between the 32nd and 39th north latitudes. 



' All the species (inoted wilbout an authority are new species described in this Repurt. 



