324 J. STANLEY GARDINER. 



consisting of blocks evidently free and some of masses showing fractures, where they had been 

 broken off the bottom or still larger lumps. 



The results were mainly negative, but the apparatus being thoroughly reliable and the 

 dredgings fairly numerous, they may be relied upon. Series of dredgings in the same locality 

 and habitat are repeatedly counted as single dredgings. 



On the opposite page is a table showing the number of times living specimens of each of 

 the different genera were obtained at various depths beyond 15 fathoms down to which the reef 

 genera extend in great luxuriance. 



The forms of growth are as follows : — B. branching : C.B. coarsely branching : F.B. finely 

 branching : S.B. spreading branches : F. foliate : /. incrusting : M. massive : S.M. spreading 

 massive : S. spreading. 



A plain cross after the name, thus f , indicates that more than one species was represented. 



The genera marked with a star * are to some extent doubtful, but serve sufficiently to 

 show the facies and alliances of the species. Domoseris is almost certainly a synonym of 

 some other genus, but I have been unable to examine any specimens of the allied genera. 



The following genera of reef-building corals, characteristic of the Maldives, are not found 

 in the collection : — Coeloria, Leptoria, Prionastraea, Mussa and Symphyllia. Goniastraea was 

 only once obtained, and the Orbicella belong to species with small calicles, not found on reefs. 

 The species of Montrpora and Hydnophora and to some extent of Astraea and Galaxea belong 

 to forms of growth widely differing from the large, characteristic, massive colonies, more generally 

 found on reefs. Madrepora with increase of depth breaks up into thinner and finer branches 

 and twigs ; its stems ramify almost horizontally, and its calicles are widely separated from 

 one another. Pocilloporu alone varies but little, its colonies presenting the same two common, 

 finely and coarsely branching, facies of growth, usually seen on reefs. 



A few genera, not found at the sui-face, are evidently of great importance as builders 

 between 20 and 40 fathoms. Of these Dendrophyllia, of which there is only one species, 

 D. ramea, where found,, appears generally to form gi-eat groves, immense quantities being 

 obtained ; some of its main branches were of large size, even 2 yards in length by 3 to 

 5 inches in diameter. An allied genus or a sub-genus, Goenopsammia, grows commonly on 

 the under, shaded sides of stones on the reef, but was not dredged. Gonipora was found 

 either as fixed, large masses, of which chijjs only were usually broken ofJ", or free in mud 

 or sand in a form allied to G. stokesi. Alveopora grew in large masses, usually much crushed 

 when brought up, or in branches, the tips of which alone were alive. Seriatopora gave 

 colonies either of extremely fine branches, or of finger-like stems. Stylophora was only secured 

 on two occasions, both outside atolls, but the quantity of massive branches then brought up 

 points to its being of no inconsiderable importance in this position. That the same genus 

 should not be found on the reefs is peculiar, as it was one of the most numerous on Funafuti 

 and other Pacific reefs. The specimens, placed under the genus Trachypora, represent modified 

 incrusting Pavonia, which have taken to a deeper habitat. 



The false corals, Millepora and Heliopora, have already been to some degree considered 

 (pp. 314—317). In the accompanying table they supply 7 out of the 14 times surface-reef 

 genera were dredged between 36 and 40 fathoms, and 3 out of 4 — the genus of the fourth 

 being doubtful — between 41 and 50 fathoms. I have never observed either of these genera on a 



