^ CORALS AND CORAL-ANIMALS. 199 



reddish or purple-brown. The conspicuous local colour variations of the tentacular filaments 

 of this handsome species have been observed to vary from light brown through golden-yellow 

 to emerald-green, their extreme tips in some instances being lemon-yellow. On being left dry 

 by the tide, the polyps of this Clavularia close like those of ordinary sea-anemones, the tentacular 

 wreath being completely retracted. Several clusters or colony-stocks of this species in their 

 high and dry, and consequently retracted, condition, are included in the photographic reef-view 

 reproduced in Plate XIX., occupying therein a position to the right-hand side in the immediate 

 foreground. 



Two smaller members of the stoloniferous section of the Alcyonaria, referable apparently 

 to the genus Cornularia, are represented in Plate X. of the chromo-lithographic series. 

 In the first of these, Fig. 22, the expanded tentacular crown is not more than a quarter 

 of an inch in diameter, and is coloured, with the exception of the light brown stolon 

 stalk bases, oral centre, and crenated edges of the tentacles, a pale sage- or beryl-green. 

 In an exceedingly minute species closely allied to the form just described, and represented by 

 Fig. 21 on the same plate, the tentacular crowns were entirely dark golden- or metallic-green, 

 suggestive in miniature, when seen in profile, of the characteristic pedicellated crest-feathers of 

 the peacock. With reference to this fanciful resemblance, it is proposed to associate this minute 

 form with the title of Cornularia pavo, distinguishing the preceding, slightly larger, type by that of 

 Cornularia glanca. A third species of the same genus, found growing in tufts on a muddy fore- 

 shore at Thursday Island, was, in the first instance, taken for a small species of Organ-pipe coral, 

 Tubipora. The apparent reddish calcareous tubuli proved, however, on nearer examination, to be 

 of corneous consistence, and united to one another, inferiorly, by a reticulated stolon. The dis- 

 tinctly developed tentacular fringe in this species was light brown, and the main shafts of the 

 tentacles, and also the peristomial disk, were yellowish-white. Representations of an expanded 

 colony-stock, and of an isolated polyp, of this type, here associated with the title of Cornularia 

 tubiporoides, are included in Figs. 9 and 10 of Chromo plate No. X. 



A very elegant little Alcyonarian, that differs somewhat from the several previously 

 enumerated species ot Cornularia, in that its tentacles are smooth and devoid of either 

 tubercles or pinnules, is delineated in Fig. 8 of Chromo plate No. III. The peristomial 

 disk in this type is a pale apple-green, the eight radiating tentacles are dark chocolate, and 

 the supporting stalks and interconnecting stolon are of a light brown hue. All efforts to 

 identify this form with some previously described species having proved unsuccessful, it may 

 be appropriately associated with the name of Cornularia auricula. 



That group of the Alcyonaria entitled the Gorgoniaceae, which includes the " sea-ferns " 

 and other allied arborescent coral-growths, whose polyps correspond structurally with those of 

 the Alcyonaria previously enumerated, is very rarely represented on the tidally-exposed reefs 

 of the Great Barrier system, almost all its members being inhabitants of deep water. A 



