90 THE VOYAGE OF H.M.S. CHALLENGES. 



Pourtales in his earlier notices referred this form to Cirripathes Desbonni, D. & M., 

 but in 1880 he described both forms, which are very distinct. This, the spiral species, he 

 referred to Antipathes spiralis, Pallas, suspecting, however, that it might differ, but 

 having no means of comparison- at the time. Both forms have a spiral habit, but this 

 of Pourtales has, in proportion to its length, a much more slender axis. It further 

 seems very probable that in the spiral species, Antipathes spiralis, Pallas, the polyps are 

 distributed spirally around the stem, in which case it comes under the genus Cirripathes, 

 as modified in the present Memoir. 



Habitat. — Off Sand Key, Florida, 45 fathoms. Very common, occurring at twenty- 

 three stations and at depths from 45 to 878 fathoms, off Havana, Santa Cruz, Montserrat, 

 Martinique, St. Vincent, the Grenadines, Granada, and Barbadoes. 



Stichopathes gracilis (Gray) (PI. XII. figs. 17-19). 



Antipathes (Cirrhipathes) gracilis, Gray, Proc. Zool. Soc. Lond., 1857, p. 291. 

 1 Antipathes (Cirrhipathes) setaeea, Gray, Ann. and Mag. Nat. Hist., ser. 3, voL vi. p. 311. 



Gray's description of this species, consisting only of the words " slender, tapering, 

 slightly spinose," is of no value whatever in the identification of the species. The speci- 

 men to which he referred is in the British Museum, its identity being made certain by 

 the reference, " Madeira, Mason, 1857," on the label. This specimen appears to have been 

 broken in two. The lower portion bearing the label, though not actually possessing the 

 dilated base of attachment, is probably the lower part of the stem, being covered for 

 three or four inches near the base by parasitic growths, and having a number of bivalve 

 molluscs attached to the axis. This portion is contorted, not spiral, and is 75 cm. long, 

 slightly tapering, and having a diameter of 2 - 5 mm. near the base. Another specimen, 

 without label, which I take to be the upper portion of the type specimen, has the same 

 wavy outbne, and is 1*1 m. long. The diameter of the lower portion of this specimen 

 agrees with that of the apex of the type. The diameter at the apex is only 0'45 mm., 

 and if my surmise be correct, the whole specimen must have measured nearly 2 m. in 

 length. 



A more recent specimen (1863) from the same locality is nearly straight, 1*3 m. long, 

 3 mm. in diameter at the base, and 1 "4 mm. at the apex. This specimen has the dilated 

 base attached to a mass of broken shells, &c. In the lower portion of the stem the spines 

 are arranged in seven rows, running almost longitudinally, but twisted in a very open 

 spiral, which requires over three inches to complete one revolution of the axis. Still 

 another specimen of this species is found in the British Museum Collection (Reg. No. 

 72.6.22.3), but whether regarded by Gray as a specimen of this species or of his Anti- 

 pathes setaeea, I am unable to say. (I have been unable to find Gray's type of Cirrhi- 

 pathes setaeea, which was described in 1860, from Madeira — the same locality as that in 



