36 THE GREAT BARRIER REEF. 



P L A T E X X I I I. 



MUSHROOM-CORflLS, FUNGM CRSSSITENTflCULHTfl. 



This plate illustrates the life aspects of one of the so-called Mushroom-corals, Fiingia 

 crassitentacidata, in various states of expansion, contraction, and development. The large, fully- 

 expanded example on the left, and the contracted specimen forming the lower figure on the right- 

 hand side, represent the same individual coral, photographed within a few minutes' interval. In 

 this last-quoted illustration, the entire outline of indurated calcareous corallum is conspicuously 

 visible, and the close association of each contracted tentacle, with the inner, centrally abutting, 

 end of its corresponding septal element, may be also distinctly traced. The expanded example 

 on the left, excepting in one minute area, exhibits no trace whatever of its coral skeleton. 

 Unaccompanied by an explanation, it might be pardonably mistaken by those familiar only with 

 the Coelenterata of the British seas for a fine specimen of the so-called Dahlia-anemone, Tealia 

 crassicornis. A photograph of this familiar species recently taken by the author in a rock-pool on 

 the Devonshire coast might, in point of fact, have been almost indistinguishably substituted for 

 the present illustration. The life-colours of this Mushroom-coral, however, vary in a direction 

 that is not shared b}' its askeletal British homologue. In no instance, so far, would it appear that 

 a brilliant green has been found associated with the Tealia. In the case of this particular 

 Mushroom-coral it represents one of the dominant tints, as illustrated by the life- coloured imprint 

 irom the same photographic negative reproduced in Plate VI., Fig. 13, of the chromo-lithographic 

 series. Rich olive greens and browns represent the additional more prevalent hues of this 

 handsome species. These ground colours, including the brighter green, are usually variegated 

 to the extent of the radiating septal lines, being indicated by conspicuous streaks of cream- or 

 primrose-yellow, while the more or less inflated distal terminations of the tentacles are white or of 

 a pale grey hue. It is noteworthy, in association with the illustration of the large specimen in its 

 contracted state, that these light-coloured capitate extremities are retracted in such a manner that 

 they present the aspect of sucking-disks or acetabulae. The tentacles of this same species in their 

 most attenuated condition are characteristically represented in the succeeding plate. 



The figure that occupies the right-hand upper corner of the plate now under notice is of 

 extreme interest. It represents a Mushroom-coral in that early stage of development in which it 

 is attached to the corallum of some distinct species of coral, or other convenient fulcrum, by a 

 distinct footstalk. After attaining to a size approximating to, or a little larger than, that of the 

 specimen figured, it becomes detached from the stalk, and lies freely at the bottom of the water. 

 In this manner the life history or ontogeny of the Fungia recapitulates, or, more correctly, 

 foreshadows, the developmental history of the Feather-starfish, Antedon, in which more highly- 

 specialised invertebrate type the organism begins its existence affixed to an elongated 



