146 THE NATURALIST IN AUSTRALIA. 
for the erect foliaceous character of its coralla, which in many instances took a very 
elegant and symmetrically convoluted scroll-like contour, and has on this account been 
associated by the writer with the title of Montipora circinata. This species was not so 
remarkable for its colour, being usually of a pale pinkish-red hue, with lighter 
edges, but was at the same time conspicuous through the circumstance of its 
growing in deep water in distinctly isolated patches of many square yards in extent. 
The more matured coralla not unfrequently attain to a height of as much as three 
feet, and, seen in masses in the crystal water beneath the boat, might be readily 
mistaken for beds of broadly foliaceous plants. A photograph of an example of this 
type, viewed vertically to illustrate its spirally convoluted growth pattern, is given 
life size in the upper half of Plate XXIV. A lateral view of the same specimen is 
also reproduced on a smaller scale in the accompanying figure. 
In connection with the subject of the Houtman’s Abrolhos Madreporide, it is 
worthy of remark that nowhere perhaps do such facilities exist for making a systematic 
record of the growth rate of tropical species as here. Many of the component 
reefs and lagoons are so sheltered and 
so readily accessible that the necessary 
measurements, observations, and experi- 
mental cultivations could be carried on at 
all seasons. In support of this suggestion, 
it may be mentioned that the coralla of 
various species of Madrepora have already 
established themselves upon the basement 
of the stone jetty constructed by Messrs. 
Broadhurst and Co. on Rat Island, in the 
Easter group, for the shipment of guano. 
Certain of these taking the form of cauli- 
flower-like clusters, and having a diameter 
of some nine or ten inches, represented, 
the writer was informed, a growth of less 
than two years; while smaller examples, 
with a diameter of three or four inches 
only, had been built up within the interval 
W. Saville-Kent, Proto, Of & twelvemonth. It is noteworthy to 
PELSART ISLAND SCROLL CORAL, Montipora circinata, 
GEES aeRO OEE observe that these Madrepora clusters were 
