﻿114 . MADEEPORAEIA. 



Coenencliyma rather firm, everywhere minutely spinuloso-asperate ; spinules ( = tubercles 

 scarcely 0"3 mm. long and never lamellata Tubercles show no special relation to the 

 calicles. 



In addition to these characters, Dana adds that the polyps are "olive-green, and the 

 tentacles obsolete." The figures given in the atlas show the corallum coloured a dark 

 slate-blue and the calicles very conspicuous ; on figure 3& the calicles are drawn with only six 

 very clear, slightly granulated septa. 3a shows a fragment of the coral with the polyps 

 retracted, the disc being radially streaked light and dark green alternately ; the tubercles are 

 few and very minute as compared with the size of the polyps, with which they stand in no 

 clear relation. 



There is no tuberculate coral in the Collection showing these characters. 



Dana's specimen was from Fiji, " Mathuata, Isle of Venua Lebu." 



89. Montipora variabilis. 



Bescription. — Corallum encrusting, thin (3 to 4 mm.), following the unevenness of the 

 substratum, worm-tubes, &c. ; edges here and there projecting free without epitheca. 



Calicles very variable, from conspicuous, deep, round holes • 5 mm. in diameter and with- 

 out any trace of septa, to minute, very inconspicuous, star-like calicles, the apertures Ijeing 

 nearly filled up %vith short thick septa belonging to two cycles. The former occur on the 

 higher portions of the corallum where the growth is most vigorous. The calicles on the under 

 surfaces of the free edges are conspicuous, and surrounded by very visible because slightly pro- 

 jecting rings of ccenenchyma, the septa being only indicated. 



The ccenenchyma in radial section shows a laminate streaming layer which, in cross 

 section, is a very open reticulum ; the lower surface forms a flat, flaky reticulum covered with , 

 very fine hair-like ecliinulas, whUe the uppermost layer tends to be rather solid, owing 

 apparently to the presence of short thick trabeculse. These rise as tubercles, which are some- 

 what stout, conspicuous and openly bushy where the growth is vigorous, but elsewhere they 

 are mostly minute foaming processes. Between the tubercles a horizontal flaky reticulum is 

 visible, which is very weU developed when the tubercles are small or absent, but very scanty 

 when the tubercles are large. The taller and stouter tubercles show a tendency to be grouped 

 in irregular rings round the calicles, which retain, however, for the most part their own 

 distinct margins. The drooping edges may have their upper surfaces either covered with 

 tubercles, or else be smooth and solid, the calicles opening in the stony surface as minute 

 stars with six very thick septa. 



There is one specimen and a fragment of this coral. Owing to the extreme amount of 

 variation which it shows, it is of doubtful value as a separate type. It might be compared in 

 t^s respect with M. erasd-tuberculata, where the same extraordinary variation is also seen. 



The type at first sight suggested Dana's scahricula, on account of the minute size and 



