484 SYDNEY J. HICKSON. 



We must remember that nearly all the specimens that are brought to Europe from the 

 tropical seas preserved in spirit are small specimens. They are probably also young specimens 

 of large species. Full-grown specimens may reach a size of 300 to 400 mm. or more in 

 diameter, but these are not easy to detach from their base of attachment, and it is, as a rule, 

 impossible to preserve them satisfactorily and send them home. 



The study of the Spom/odes collection from the Maldives throws, however, a little light on 

 one or two points of general interest. 



In the first place we find in this one archipelago a very wide range of variation. The 

 colour of the spicules varies fi-oin pure white (as in the specimen from Kolumadulu) through 

 many shades of yellow, orange, brown, pink, red, pui-ple, chocolate to black (as in the stalk of 

 the specimens from Fadifolu). 



In some forms the spicules are enormously large, in others they are relatively small. 



A few forms with very divaricate branches are found, but others have a remarkably compact 

 habit of growth. 



These differences are not more pronounced between specimens found in the extreme north of 

 the archipelago and those in the extreme south. On the contrary, the specimens from the same 

 atoll are sometimes most diverse in colour. For example, the large coarse golden-yellow specimens 

 from N. Male, 20 fathoms S.W. of the atoll, are in marked contrast to the delicate chocolate- 

 coloured specimens from 24 fathoms in the shoal at the centre of the atoll, and the pale 

 yellow form, like Spongodes Jlahellifera found in the S. atoll in 25 fathoms. Three small speci- 

 mens from Hulule Male, 25 to 30 fathoms, are so much alike in colour, spiculation and size of 

 anthocodiae that they clearly belong to the same species, and yet they are of such different form 

 of growth that they might be delegated to different divisions of the genus. The specimen from 

 Miladumadulu in the north of the archipelago is very closely related to the single specimen 

 from Addu in the extreme S. They are much more closely related than are the two dusky- 

 brown specimens and the two red divaricate specimens which were obtained in the same dredging 

 in the Fadifolu atoll. There is nothing to show that geographically there are any limits to 

 the distribution of the .species within the archipelago. There are probably no characteristic 

 features distinguishing the Spongodes of one atoll from that of another. But we can go further 

 than this and say that there are no characteristic features which appear to distinguish the 

 Spongodes of the Maldives from those of suitable localities in the other regions of the Indian 

 and Pacific Oceans. There are specimens from the Maldive archipelago that clearly belong to 

 the same species as specimens in my collections from Singapore, New Britain, and Fiji. There 

 can be no doubt that .specimens are present in the Maldives, which under our present system 

 would be referred to Holm's species (13) Spongodes spinifera, founded on a specimen obtained 

 in the Fiji Islands, to Kukenthal's species (15) Spongodes splendens, founded on a specimen 

 obtained in Ternate, to Studer's species (22) S. fiabellifera, obtained in Japan. 



All these facts appear to me to point to the conclusion that the species of the genus 

 Spongodes are extremely variable, and have a very wide geographical range in tropical waters. 

 Whether there is only one true species is a question to which with our present want of exact 

 anatomical knowledge no answer can be given. I am convinced, however, that the characters 

 upon which new species have been founded in recent years in such large numbers are untrust- 

 worthy for the purposes. 



Two lines of inquiry might yield interesting results. Firstly, there should be a careful 



