Ho8 REPORTS ON THE STATE OF RCIEXr'E. 



The Soycliellos Bank comprises about 21,000 S(iuarc uiiles within tlio 

 100 fathom line, with an average depth of 30 fathoms. Its outer slope is 

 similar to that of the other submerged banks we visited, but a rim is 

 indicated only to the north-west in a series of shallower soundings, 

 to 1 5 fathoms, and in two typical surface reefs with coral islets, Bird and 

 Dennis. Th(i greater part of the bank appears to be relatively bare, being 

 strongly swept by tidal and other currents. In the centime arises an 

 archipelago of small islands, of whicli Maht', Silhouette, and I'raslin are 

 the most important, attaining heights respectively of 2,993, 2,467, and 

 1,261 feet. They together cover about 150 square miles, and are all 

 formed of similar coarse granites, with narrow, vertically extending dykes 

 of finer-grained, black vai'ieties of the same. Many of the bays have flat.'! 

 of sand, largely coralliferous, some washed up from the sea, and others 

 really of delta formation. But in places there is evidence of a recent 

 upheaval of 30 to 40 feet, and in Maht- there are indications of an ancient 

 elevation of about 200 feet. 



Barrier reefs nowhere exist around the islands, and fringing reefs only 

 in bays or protected situations, whereas they might be expected to occur 

 everywhere. Examining the coasts, we found a luxuriance of coral 

 growth, but practically a complete absence of nullipores. Indeed, these 

 calcareous alga; are essential in the Indian Ocean for the consolidation of 

 corals into true reefs. Where fringing flats actually occur, they consist 

 of a basis of granitic rock with quite a sparse covering of calcareous 

 matter, or are a filling in with the remains of reef organisms betsveen 

 masses, or islets, of granite and the main islands. Boat passages are the 

 outfalls for the tide, and show no connection with fresh-water streams oB" 

 the land, beyond the fact that the latter have, in many places formed the 

 l>ays, where they happened to exist. Finally, it is interesting to note 

 that the actual surfaces of the flats are covered with a far greater variet)' 

 of large seaweeds than we found in any of the purely coral groups W6 

 visited in the ' Sealark.' 



Tim Collections, Sc. 



The collections obtained by the expedition comprise a large series of 

 land and marine organisms, both animals and plants, besides water 

 samples and geological specimens. The waters are in the hands of Mr. 

 D. Matthews, who has also about 2,000 samples collected by various liners 

 in the Indian Ocean ; while the crystalline rocks have been undertaken by 

 Mr. Flett, of the Geological Survey. The land and fresh-water animals 

 have been sorted, and so far the following groups have been sent out for 

 determination : Mammalia (Mr. Oldfield Thomas, F.R.S.), Aves (Dr. 

 (iadow, F.R.S.), Reptilia, Amphibia, and Pisces (Mr. G. A. Boulenger, 

 F.RS.), Mollusca (Mr. E. R. Sykes), Coleoptera (Dr. Sharp, F.R.S.), 

 Rhynchota (Mr. W, L. Distant), Hymenoptera (Mr. P. Cameron), Odonata 

 (Mr. F. F. Laidlaw), Lepidoptera (Mr. Bainbrigge Fletcher), Myriapoda 

 and Arachnida other than spiders (Mr. R. I. Pocock), Acarina (Professor 

 Newmann), Decapoda (Mr. L. A. Borradaile), Chtetopoda (Mr. A. E. 

 Beddard, F.R.S.), Nemertea (Mr. R. C. Punnett), and Turbellaria (Mr. 

 F. F. Laidlaw). The land plants have been undertaken by Mr. J. C. 

 Willis, and the ma^rine sdgx (not lAthothamnion) by Mr. and Mrs. Gepp. 



The .sea animals comprise a vast number of forms, both bottom-living 

 and floating. Only the Nudibranchiata (Sir Charles Eliot, K.C.M.G.), 



