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



pairs, which are a considerable distance apart, the two forming an apparent pair being 

 close together on opposite sides of a branch. According to the view which I have taken 

 of the homologies of the mesenteries, the lateral pairs must, however, be considered to 

 consist of two tentacles on the same side of a branch, that is to say, a pair of lateral 

 tentacles is situated on each side of the pair of transverse mesenteries, and the greater 

 the elongation of a polyp the more the two tentacles, which morphologically form a pair, 

 become removed from one another. The mouth is somewhat elongated in the sagittal 

 axis, but the stomodseum, particularly in its lower part, has frequently a greater diameter 

 in the transverse than in the sagittal direction. There are ten mesenteries in the oral 

 cone and six below. The transverse pair of mesenteries are very long, and correspond to 

 the elongation of the zooid. The peristome usually presents a slight depression on each 

 side of the oral cone where, the transverse mesenteries are partly reduced, but there is no 

 indication of a vertical mesogloeal septum as in the Schizopathinse. The reproductive 

 elements are borne only on the distal portions of the transverse mesenteries. The spines 

 are short and very distant, frequently appearing like short pointed tubercles, but at 

 other times they are longer, and triangular or hooked upwards. 



The corallum in the type species and also in Antipathes tetrasticha, Pourt., which 

 probably belongs to the same genus, consists of a simple or rarely branched stem with 

 simple spiral or verticillate branches. It is interesting to note that another species 

 (Aphanipathes ? harbadensis, n. sp.), the polyps of which are not known, has a similar 

 form of corallum, but the spines are of such a different character that in the absence of 

 more definite information I have considered it necessary to refer it to another genus. 



Parantipathes larix (Esper) (PI. XII. fig. 20 ; PI. XIII. fig. 2 ; PL XV. fig. 1). 



Antipathes larix, Esper, Pflanzenth., Fortsetz., pt. ii. p. 147, pi. hi.; Lamarck, Hist. nat. anim. 

 sans vert., t. ii. p. 308 ; Lamouroux, Polyp, flex., p. 374 ; Encycl. method., t. iv. p. 70 ; 

 Eisso, Hist. nat. de l'Europ. meridionale, t. v. p. 3.30 ; Blainville, Manuel d'Actinol., p. 551; 

 Dana, Zooph., p. 577; Milne-Edwards, Coralliaires, t. i. p. 315; Gray, Proc. Zool. Soc. 

 Lond., 1857, p. 292; Lacaze Duthiers, Ann. Sci. Nat. (Zool.), ser. 5, t. iv. pp. 49-52, pi. iv. 

 figs. 23-25; v. Koch., Morph. Jahrb., Bd. iv. pp. 74-78, pi. i. 



Stem erect, simple, or rarely branched near apex, bearing six rows of close-set, 

 spirally arranged, simple pinnules, almost at right angles, each row in a plane. Spines 

 short, distant, subcorneal, and often hooked upwards, not all of the same size. 



The largest specimen with which I am acquainted (Brit. Mus. Coll.) measures 1*3 m. 

 in length, and has a diameter of nearly 8 mm. at the base. In this specimen the stem is 

 unbranched, and maDy of the pinnules are over 12 cm. long. In another specimen, 0*5 m. 

 long, the pinnules average 3 "2 cm. in length, but in the middle portion they are subequal 

 and about 3*5 cm. long. The pinnules are straight, rigid, filiform, and pass out almost at 



