MADBEPORARIA. 773 



in the columella and in the nature and shape of its septa, but their upper edges over the 

 theca are often rather pointed than flattened. The pali are the thickened, perpendicular, 

 inner edges of 8 — 12 septa. The endothecal dissepiments are thin and practically horizontal, 

 generally '5 — "6 mm. distant, seldom or never more. The walls in section are about 2 mm. 

 thick, but on the surface in any rapidly growing part may be quite thin, evidently thickening 

 later by a deposition of solid endotheca between the septa. 



Locality. A single specimen from the passage at Hulule. It is No. .5, p. 331 of Vol. i. 

 of this publication ; its specific gravity 21 1 is greater than that of any other Astraeid that 

 I have taken. 



32. Goniastraea pectinata (Ehrb.). Klz., p. 34, iv. 6. 



Three specimens, the third very small, are undoubtedly referable here, though Ehrenberg's 

 specimen is, I consider, scarcely tyjiical of the species. The luall is thin, though the whole 

 ridge with its very slightly exsert (never more than 5 mm.) septa, horizontally edged above, 

 varies from 2 to 4 mm. The septa are occasionally very thin, but in most parts, to the lens, 

 appear rough-sided and relatively thick ; they are more often continuous between calices than 

 alternating, and are subequal in size, but in some places very rudimentary ones of cycle IV. 

 are found between the larger. The pali are rough sided plates in front of, but not in 

 surface view connected with, the septa; their number varies with the length of the corallites, 

 but in rounded calices their mode is 10 or 11. At the edge and on the under side of the 

 colonies the walls may become much thicker, but the whole ridge (including the septa) varies 

 but little; the pali sometimes are spiniform. The columella is merely the junction of the 

 paliform septa to one another, and may be scarcely visible, plate-like or obviously formed 

 by flattened trabeculae. 



Locality. Goidu, reef-flat, Turadu, S. Mahlosmadulu, flat behind boulder zone, and 

 S. Male, 18 /. The latter is a little colony with 3.5 rather shallow calices, with very thick 

 walls (3 mm.) having traces of a grove. 



33. ? Goniastraea favus (Forsk.). Klz., p. 34, iv. 4 and x. 7. 



The broken-off edge of a colony, 7'5 x 3 cm. by 4 cm. thick, possibly belongs to this 

 species, with the characters of which it is in general agreement. It does not show clearly 

 its mode of increase though sections lead me to believe that it is by fission. The specimen 

 was dredged from 20/., Suvadiva. 



XIII. Genus Aphrastraea. 



34. Aphrastraea deformis (Lmk.). (PI. LXIII. fig. 31.) Ed. and H., ii. p. 452. 



I refer four specimens to this species, nos. 1 and 2 of which agree closely with one 

 another and con-espond in all described characters with the species and also genus, of which 

 it was in Ed. and H.'s catalogue the sole representative. The walls have a distinct theca 

 which may show as a very thin, polygonal ridge between the calices, but their gi-eater part 

 is formed by the small vesicles or cells of the endotheca, which rise to within '5 mm. of 

 the upper edges of the septa ; they thus appear enormously thick up to 5 mm. The septa 

 are continuous between the calices or stop at the theca; they lie in four cycles of which 

 I. and II. typically have rough upstanding, pointed, paliform lobes, though II. is not in this 

 re.spect always complete. Septal cycles III. and IV. are scarcely separable and mere little 



99—2 



