BY C. HEDLKY. 461 



for study, and the lower produced almost all the new or remark- 

 able shells noticed in the following pages. The sea-floor over 

 which we dredged in a uniform depth of 17-20 fathoms, consisted 

 of masses of living coral ; budding reefs in fact, with intervening 

 spaces of coarse sand and gravel, and here and there dense beds 

 of kelp. 



Various plant societies are termed in botanical language, 

 " formations," thus a heather formation, a pine formation or a 

 mangrove formation. We cannot adopt this nomenclature and 

 express the mollusca associated with coral reefs as a "coral 

 formation," because that term is already appropriated by geologists 

 for a different meaning. Let us call it a madreporic assembly. 



The first panoramic view of the coral-haunting mollusca was 

 presented to science by the collection made by Hugh Cuming 

 in the Paumotus. The following passages suggest the impression 

 that the madreporic assembly characterises a geographic province, 

 instead of being, as is really the case, a consequence of the special 

 environment of clear and warm water. 



"In the animal kingdom" Jukes* "was struck with the 

 difference in the general aspect and character of the shells and 

 echinodermata collected about Cape York and those got near 

 Erroob." . . . " It was evident that in crossing Torres Strait 

 we were passing from the Australian centre of life, so to speak, 

 into that of the Indian Archipelago, or more strictly perhaps, of 

 the Moluccas." 



Mr. E. A. Smith wrotef of the marine mollusca of the Maldive 

 coral reefs: — " It is curious to observe that a larger proportion 

 of them have been previously noted from . . . the Pacific, 

 than from the Indian Ocean." 



An account of the Crustacea [ante pp. 2-53, Pis. i.-iv.) by Messrs. 

 Grant and McCulloch has already been issued. Representatives of 

 other groups have been handed to various specialists, and it is 

 hoped that further reports on them may appear. We were 



* Jukes, Voy. 'Fly, i. 1847, p.298. 

 + Smith, Fauna Maldive, Laccadive Archipelagoes, ii. 1905, p.589. 



