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MADREPOKARIA. 



Specimen h (PI. V. fig. 3) is a tliia-stemmed specimen, with the tips also tending to form 

 clusters of thin tapering processes, fusing irregularly together. The whole stock is compact, 

 squat, and laterally expanded. 



The third specimen c (PI. V. fig. 2) is composed of tall, thin, curved stems, recalling Dana's 

 type tortuosa. The locality of this specimen is unfortunately not recorded. 



I have figured these three specimens to illustrate the degree of possible variation of 

 groAvth-form in one and the same species. 



a. Eaniesvaram, Giulf of Manaar. 

 h. Eamesvaram, Gulf of Manaar. 



c, d, e. Locality not recorded. 



E. Thurston, Esq. 88. 11. 25. 5. (Type.) 



88. 11. 25. 4. 



114. 



Eegister Nos. 97. 6. 18. ] 15. 



16. 



34. Montipora rotunda. (PL IV. fig. 4; PL XXXII. fig. 4.) 



Description. — Corallum a massive round-oval stem, 4 by 3 cm. thick, the top swollen up 

 and irregularly knobbed and lobed. 



Calieles conspicuous, very uniformly distributed about 1 diameter apart, 0*75 to 

 1 ■ mm., slightly sunk, very irregular apertures, six irregular septa. 



Ccenenchyma consists of an almost solid axial portion, surroimded by dense reticulum in 

 which concentric solid rings can be recognised ; these perhaps mark off the successive growths. 

 In the outermost layer of the reticulum, radial elements are distinct ; these appear to be 

 confined to the coloured (orange-yellow) zone, which is 3 • 5 mm. thick. The slight formation 

 of a solid layer along the inner edge of the coloured zone suggests that this was the limit of 

 the living coral. On the surface, the ccenenchyma shows as an open network remarkable for 

 its very angular, sometimes rectangular meshes, the threads of which it is composed being 

 short and straight, but bent sharply at all angles with one another. This reticulum necessarily 

 makes the outlines of the calieles very irregular. All the interstices seem to be slightly swollen 

 up convexly. 



It is difficult to decide whether this specimen should be classed with the foveolate or with 

 the glabro-foveolate group. There is a sweUing of the interstices, but it is not very prominent. 

 It is best seen on the uppermost gTowing surfaces of the knobs or lobes. 



The peculiar angular reticulum gives a unique and coarse look to this Montipore, which is 

 also remarkable because of its continuous growth in thickness. It is thus at the same time 

 both massive and branched. 



a. Palm Island, Great Barrier Eeef 



CoU. SaviUe-Kent. [92. 12. 1. 9.] (Type.) 



. 35. Montipora spatula. (PL IV. fig. 3 ; PL XXXII. fig. 8.) 



Description. — Corallum is a tuft of broad, flat, erect branches, irregularly fused, rising at 

 least 15 cm., dying down below, the living zone being about 7 cm. deep. Each branch tends to 



