KEPORT ON THE ALCYONAlllA. xlv 



7. Primnoisis, Wright and Studer, Arcliiv f. Naturgesch., Jahrg. liii. Bd. i. p. 46, 1887. 

 The colony is branched in several planes, the polyps arising at wide intervals and 



beinor spirally arranged. In the polyps tlie calyx scales are large, and the mesenteric 

 folds are crowded with small spicules. 



8. Mojysea, Lamouroux, Hist, des Corall. flexibles, p. 468, Caen, 1816. 



The colony is branched in one plane. The polyps are small, club-like in form, and 

 arranged in dense spirals round about the stem. The calyx scales are small, short, and 

 spiny. 



9. Acanthoisis, Wright and Studer, Archiv f. Naturgesch., Jahrg. liii. Bd. i. p. 46, 



1887. 

 The colony is branched and expanded, fan-like in one plane. The polyps are 

 inconspicuous, cylindrical in form ; when contracted the apical region is truncated. The 

 calyx scales are short and spiny. The internodes are furrowed, with dentated ridges. 



Subfamily 3. Isidin^. 

 The colonies are branched, with a thick coenenchyma, within which the polyps can be 

 wholly withdrawn. The spicules are radiately stellate and covered with rough warts, of 

 which there may be six, eight, or twelve on each. Some simple club-like forms also 

 occur. This subfamily contains but the one genus — 



10. Isis, Linneus. 



Family VII. P R i M N o I D ^. 



rrimnoaceic (pars), Valenciennes, Comptea reudus, t. xli. p. 7, 1855. 



Primnoacex (pars), H. Milne-Edwards, Hist. Nat. des Coralliaires, t. i. p. 188, 1857. 



Primnoadx, Gray, Proc. Zool. Soc. Lond., 1857, p. 285; Op. nt., 1859, p. 483. 



Frimnoaceee (jjars), as a division of subfamily Gargonin*, Kolliker, Icones histiologicaj, pt. ii., 



1865, p. 135. 

 PrhmwidiE (^)a;>), Veriill, Trans. Connect. Acad., vol. i., 1869, p. 418; Revis. Polyps East 



Coast Norch America, Mem. Boston Soc. Nat. Hist., vol. i., 1884, p. 8. 

 Prininoadx (pars), Calliijorgiadx (pars), Calijptr,jplioridx, Gray, Cat. Lithophytes Rrit. Mus., 



1870, pp. 34, 41, 43. 

 Primnoadse (subfamily), Studer, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, 1878, p. 641. 

 Pi-imnoidx (emend.), Verrill, Bull. Mus. Comp. ZouL, vol. xi. p. 28, 1883. 



Holaxonia with a calcareous and horny axis, basal attachment always calcareous. The 

 polyps with a projecting, usually club-shaped calycinc portion, tentacular portion retractilt;. 



(gooL. CHAii.. EXi'. — PART LXiv. — 1889.) . Sss ;? 



