PHOTOTYPE PLATES NOS. XVI. AND XV 11. 27 



side is flattened, widely-expanding corallum of Madrcpora surcnlosa. Many other coralla of 

 this variety are visible on the reef, and notably a large isolated example well out to sea, near the 

 centre of the picture. Growing at a lower level than, and a little to the right of, the foreground 

 specimen, is a semi-submerged corallum of Madrepora gcmniifcra, a species conspicuous for its 

 brilliant and varied tints. In some examples observed the corallum was bright violet through- 

 out, with a tendency to magenta towards the tips of each separate branchlet; in others a creamy 

 hue predominated, with violet or crimson extremities and growing points ; while in a third 

 series, the ground colour varied from light to dark sage-green, all the growing points, as in the 

 preceding instance, being violet or crimson. Two of the digitiform branchlets of this species, 

 embodying the conspicuous colour-variations last mentioned, are represented by Figs. 9 and 

 10 of the Chromo plate No. IX. 



The numerous other specific varieties of this same genus that are visible on this reef include, 

 among the bouquet-shaped corymbiform series, Madrcpora australis, nullepora, digttifcra, and 

 Hcmprichi. Of the bush-forming, or Stags'-horn varieties, a luxuriant growth is conspicuous 

 along the inner margin of the reef. The most massive coralla of this series, near the foreground 

 centre, represent ?ifadrcpora graiidis, a species of which the ground colour is commonly bright 

 yellow. A variety, of a light straw hue, with delicate lilac terminations, was obtained at 

 the Palm Islands. A small terminal branch of the more ordinary yellow corallum of this 

 species is included in the coloured plate last quoted. The very massive proximal, or basal, 

 ramifications of this robust coral may be as much as three inches in diameter. Madrcpora 

 decipiens, mtiricafa, Iicbcs, pukhra, representing forms enumerated in association with previous 

 illustrations, assist to swell the list of specific types that flourish on this luxuriant reef. The 

 genus Pocillopora is abundantly represented in this reef-view, by the cosmopolitan variety 

 P. daniicornis ; a few coralla of massive Astraeaceae are also visible. Among the latter, an 

 abnormally smooth, hemispherical corallum, probably that of a Cyphastraea, occupies a central 

 position on the reef, a little towards the right. 



PLATE XVII. 



CRESCENT REEF, OUTER BIRRIER SERIES, NO. 7. 



This reef-scape represents an end-on view of the outermost portion of the area included in 

 the preceding plate. On comparing the two, several of the more prominent coral-stocks will be 

 recognised as occupying conspicuous positions in both pictures. The hemispherical sub-central 

 Cyphastraea is one of these, and also the fine corymbiform corallum of Madrcpora australis that 

 forms the principal coral-growth on the left-hand side of the immediate foreground. An 

 enumeration of the associated varieties would be but a repetition of the description oi the pre- 

 ceding plate. There is one, more diminutive, thickly branching species of Madrepora, however. 



E 2 



