REPORT ON THE ANTTPATHARIA. 21 



group. It will, however, be interesting to ascertain what precise bearing the new facts 

 here brought forward have on the arrangement of Milne-Edwards from two points of 

 view. First it will be instructive to ascertain whether in the light of more recent 

 researches it will be possible to retain the generic names given by Milne-Edwards, and 

 secondly we may arrive at some conclusion as to how far a particular mode of branching 

 appears to be ef generic value. Fur this purpose it appears more convenient to consider 

 the more restricted genera first. 



Arachnopathes. — The following is Milne-Edwards' definition of his genus Arach- 

 nopathes : — " Axe sclerobasique se divisant en une multitude de branches tres greles 

 que se dirigent en divers sens et se soudent entre elles aux points de rencontre, de 

 facon a constituer des reseaux dont la reunion forme une touffe arrondie. Tissu 

 sclerobasique noir et opaque." He includes only two species, viz.: — Arachnopathes 

 ericoides (Pallas), and Arachnopathes clathrata (Pallas). If I have been correct in 

 my identification of the former species, its mode of branching is precisely that described 

 by Milne-Edwards, and the whole corallum lacks the apparent flatness shown in Esper's 

 plate. A small fragmentary specimen in the British Museum collection may be the 

 Antipathes clathrata of Pallas, but if so does not show the marked difference in 

 thickness between the branches and branchlets to which Milne-Edwards refers. This 

 specimen agrees with the former in consisting of a thick dense mass of branchlets 

 all fused into one firm network, but there is not the same marked spiral arrangement of 

 the branchlets as in the former species. A third form here described as new {Arachno- 

 pathes aculeata) has precisely the same thick matted corallum as the two former 

 species, but in this case the branchlets, although frequently collected into groups, are 

 chiefly confined to one margin of the branches. These three species undoubtedly have a 

 peculiar form of branching in common, and one, too, which is not found in any other 

 described species, so far as I have been able to make out from the frequently scanty 

 descriptions available. The polyps are not knowm in any of the species, so that whether 

 in this case a particular type of polyp is associated with this peculiar corallum, I am 

 unable to say at present. A much branched type in the Challenger collection 

 {Antipathella contorta) is certainly in some respects closely allied to Arachnopathes 

 clathrata (Pallas). It shows the same marked contrast between the thickness of the 

 branches and the innumerable needle-like branchlets which spring from them, as is 

 figured by Morison (6). In the Challenger species, however, there appears to be no 

 regular fusion between the slender branchlets in the manner indicated by Morison. 

 The polyps of this species do not appear to differ in any important respect from those 

 of other members of the genus Antipathella. I have not seen a specimen which I could 

 with certauity refer to Arachnopathes clathrata (Pallas), and, so far as I am aware, it 

 has not been identified by subsequent investigators. A specimen in the British Museum, 

 which agrees fairly well with the original description, does not show such a marked 



