28 BULLETIN OF THE 



.28 by .02, .24 by .03, .18 by .02 mm.; those of the coenenchyma, .50 by .02, 

 .38 by .015, .22 by .015 mm. 



Station 190, in 542 fathoms, off Dominica, and Station 173, in 734 fathoms, 

 off Guadeloupe, 1878-79, Blake Expedition. 



Family PRIMNOID^ (emended). 



PrimnoadcE (pars) Gray, Proc. Zool. See. London, 1857, p. 285; 1859, p. 483. 

 Prinmoidce (pars) Verrill, Kevision Polyps E. Coast N. Am., in Mem. Bost. Soc. 



Nat. Hist., L, 1864, p. 8 ; Trans. Conn. Acad., L, 1869, p. 418. 

 Primnoad(z (pars) -^-Calyptropkoradce -i-Calligorgiadie (pars) Gray, Cat. Lithopliytes 



Brit. Mus., 1870. 

 Primnoadie (subfamily) Studer, Monatsb. Akad. Berlin, for 1878, p. 641, 1879. 



This family should, properly, be separated from Muriceidce, and restricted so 

 as to include only those genera in which the spicula of the coenenchyma and 

 calicles are scale-like and the axis more or less calcareous, at least in the main 

 stem. The calicles are usually elongated and pedunculated, or narrower at 

 base than at summit; they are frequently closed at the summit by eight oper- 

 cular scales. In most of the species the calicles are arranged in whorls, which 

 are often closely «rowded, but in some cases they are in two simple, alternating 

 row.s. The Muriceidm differ in having the axis entirely horny, and in having 

 large fusiform or spiniform spicula. Gray erroneously included in his Prim- 

 noadse Swiftia and TJiesea, which have the axis horny and the spicula not 

 scale-like ; Riisea, which is closely allied to Verrucella and Gorgonella ; and 

 Chrysogorgia, the type of a distinct family. In his Calligorgiadce he errone- 

 ously included Scirpcaria, Nicella, and Raynerella, which are closely allied to 

 Verrucella. There is no good reason for separating the three groups named by 

 him. 



Primnoa Pourtalesii Verrill, sp. nov. 



Plate II. Figs. 3, 3 a - 3 e. 



The coral is plumose, with regularly pinnate branchlets, all in one plane. 

 Near the base there are several divergent branches, like the main stem. The 

 stem is compressed in the same plane with the branches, and is a little bent 

 in zigzag between the branchlets. The branchlets are very regular, slender, 

 straight and nearly parallel, alternating on the two sides, and diverging at an 

 angle of about 45° from the stem. T^ey bear the calicles in two close, regu- 

 lar, alternating rows. The calicles are elongated, expanded at the summit, 

 and curve a little upward and forward, so that the openings all face the 

 front side of th6 coral; they are elegantly clad in a covering of small imbricated 

 scales, forming several rows, and the aperture is closed by eight regular, con- 

 vergent, triangular scales. Along each side of the main branches there is also 

 a row of similar calicles, usually two on each side, between the bases of suc- 

 cessive branchlets. 



