776 J. STANLEY GARDINER. 



view, separating furrow naturally very marked. Costae low, thick and broad, alternately thicker 

 and thinner, hence in two series, the thinner very commonly with no corresponding septa 

 visible, all set on thtur edges with low, transversely extending granulations. Septa, 35 — 40 in 

 number, alternately larger and smaller, yet both series varying somewhat in size, roughly 

 granular at the sides, 1 — 2 mm. exsert, all rather thickened on passing into the theca, here 

 and there septa of the second series curving towards and uniting with one of the first : edges 

 sometimes no distinct teeth, sometimes about six low, rough ones, generally about 15 with 

 prominent, broad (1 mm.), thicker, uprising paliform teeth forming a definite crown. Columella, 

 2 — 3 mm. below the paliform crown, -\ — ^ of the calice in width, flat above, formed by rather 

 coarse, flattened trabeculae from about half of the septa. In section, the theca of the caliees 

 very distinct, costae often continuous, exothecal dissepiments horizontal, thin, 1 mm. apart ; 

 endothecal dissepiments thin, about 1 ram. apart, almost horizontal, in transverse section not 

 more than one visible between the theca and the columella. Increase generally by inter- 

 calicinal budding, occasionally intra-calicinal close to the margin, very rarely fission. 



The species is very distinct from all previously described. There can be no doubt about 

 its being an Orbicella, but it closely resembles in its corallites some of the tubuliferous 

 Favia. The fact that the costae are about twice as numerous as the septa (about 76 to 42 

 in large caliees) is most characteristic, but in places near the edges the septa and costae 

 often become quite thin, the smaller series of costae almost absent, paliform lobes little 

 marked and corallites less projecting. 



Locality. Breaker zone of reef-flat close to Ragandi Islet, Minikoi. 



39. Orbicella ?curta Dana. Zooph. p. 209, x. 3, Gard., p. 754. 



A small fragment from N. Mahlosmadulu, 4 /!, comes near this species, but the septa are 

 rougher toothed and moi'e equal. 



40. Orbicella (Leptastraea) immersa Klz. Klz., p. 47, vi. 1. 



A rounded mass, 7 cm. long, once completely covered by living polyps, now dead in places, 

 certainly belongs to this species, though the caliees are in parts slightly smaller with rougher 

 septa. 



Locality. From the passage at Hulule. 



41. Orbicella (Leptastraea) ehrenbergana (Ed. and H.), Klz. 



Ed. and H., ii. p. 494, D. 7. 4, Klz., p. 46, vi. 3 and Leptastraea transversa Klz., p. 46, 

 VI. 2, Orbicella klunzingeri Gard., p. 755. 



Nineteen specimens, some of which agree absolutely with the one description of Klunzinger 

 and some with the other, but most of which are intermediate in some of their characters. Ed. 

 and H.'s description and figures differed so widely from Klz.'s that I did not consider that 

 these authors were referring to the same species when I examined ray collections fi-om the 

 Pacific. My present large series, together with my two Pacific Ocean specimens, shows the 

 variation to be so great that there can be no doubt of the identity. 



It appears to me useless to attempt to re-describe the species from any central form, 

 especially as any large collection is likely to have forms almost exactly similar to Klz.'s 

 ehrenbergana or the same author's transversa from precisely the same locality or even 

 environment, certainly at any rate from the breaker zone or flat of any reef. Yet, in certain 

 caliees of these forms variations may be found connecting them together, though one part of 



