326 



DE. G. J. HINDE. 



Madreporaria Perforata. 



Genus Madrepora, Linn. 

 This genus is the most common and widely distributed of all the corals in the 

 borings at Funafuti. In the Main Boring it is present very generally from the 

 surface down to 150 feet, and many of the solid cylindrical cores are nearly entirely 

 composed of masses of it in position ot growth. Then there is an interval of over 

 200 feet, in which it has not been noticed; it reappears at the depth of 375 feet, 

 and extends, with occasional breaks, to the bottom of the boring. In the Second 

 Boring (D) it is equally as prominent as in the upper part of the Main Boring. It 

 is probable that several species are represented in the cores, but, with one exception, 

 they are not sufficiently preserved to allow of satisfactory diagnosis and comparison 

 with recent forms of the genus. The exceptional species is very abundant, and the 

 examples of it from the cores near the surface are in good condition ; it possesses 

 certain features, more particularly an unusual development of the coenenchyma, 

 which distinguish it from any recent form with which I have been able to compare 

 it. I have, therefore, been constrained to regard it provisionally as a new species, 

 and have referred to it in this report under the name of Madrepora contecta. Its 

 characters are given below. 



Madrepora conteda, up. n. Corallum consisting of a massive base, from which robust, dichotomous 



branches are given off. The branches are 8-22 millims. 

 in diameter, they have a generally upright direction, 

 and they diverge at acute angles. The outer surface 

 of the branches is longitudinally or obliquely striate. 

 The interspaces lietween the branches are occupied by 

 a growth of laminate ca?nenchyma, which completely 

 envelopes the branches and binds their lower portions 

 into a continuous mass. 



The axial corallitcs are sub-circular, 4-4-5 millims. 

 across, the walls are thick, the calicinal aperture is about 

 1-3 millim. wide, and there are twelve septa. The 

 radial corallites are thickly grouped round the axial, 

 they are 2-2'5 millims. in thickness, the calices are 

 about 1 millim. in width, with six to ten septa ; their 

 fiee distal ends are not shown in the specimens from 

 the cores, hi the coenenchyma there are numerous 

 fully immersed corallites, at varying distances apart, 

 sometimes separated by less than their own diameters, 

 at others very sparsely scattered; they are elongate, 

 cylindrical, the walls are simple, the calices 0-75-1 millim. 

 in width, with weak curved septa, and at intervals 

 they are traversed obliquely by dissepiments or tabulae. 



The coenenchyma consists of a series of thin, horizontal, 

 or slightly arched platforms or layers, supported by 

 numerous vertical spines or pillars ; the layers are 

 about 0-26 millim. apart, and in places imperforate, 



Fig. 21. — Part of a transverse section of a mass 

 of Madrepfffa conteda, showing the branches of 

 the coral completely surrounded by the lami- 

 nate coenenchyma. Enlarged 1-| diameters, 

 nearly. 



PVom the JNlain Boring, core 52, depth 40- 

 50 feet, slide 619. 



