388 
THE VOYAGE OF H.M.S. CHALLENGER. 
Of the Liisitanian province: — Thenea schmidtii, Calthropella geodides, Ancorina 
cerebrum and Ancorina wageneri, Pa'pyrula candidata, Caminus vulcani, Corticium 
candelahrum, Thrombus ahyssi, Corallistes masoni and Corallistes howerhankii, may be 
regarded as characteristic. 
Of the Caribbean : — Thenea fenestrata, numerous species of Geodiid sponges, 
including Placosjpongia intermedia and Isops {?) apiarium, are characteristic ; Corticium 
candelahrum of the Lusitanian province is here represented by Corticium versatile ; the 
species of Tetillidse appear to be distinct, and one marked feature is the rich development 
of Lithistida, the species of which are distinct from those of the Lusitanian province. 
Of the Brazilian : — Craniella carteri, Caminus spheroconia, Cydonium glariosum, 
Synops neptuni, and Synops vosmaeri, are all peculiar and well-defined species. The 
remarkable Trihrachium schmidtii occurs both in this area and in the Caribbean. 
The four species from the Magellanic province are all peculiar and characteristic ; 
several specimens of Cydonium magellani were obtained from two stations, so that it is 
probably a common form. 
From the South African province the Challenger did not obtain any Tetractinellida, 
although several new and interesting forms of Monaxonida were brought to light. Two 
species of Choristida had been previously obtained from the Cape, however, and these are 
both peculiar, one — Tetilla casula — being a remarkable and extremely interesting form. 
Of the Indo-Antarctic province all the species are distinct ; they include the peculiar 
Cinachyra barhata, n. gen. et sp., and the exquisite Thenea delicata; of the former 
species about fifty specimens were obtained. 
Of the Indo-Pacific province : — The genus Myriastra appears to be very characteristic, 
though it is not confined to it, one species occurring in the Lusitanian. The genera 
Disyringa and Aurora are confined to it. Well-marked and peculiar species are Tetilla 
merguiensis, which ranges from Torres Strait to Mergui, Burmah, Tetilla pedifera, 
Chrotella macellata, Thenea wyvilli (a very distinct form of Thenea, occurring in 
comparatively shallow water), Myriastra clavosa, Aurora globostellata, Disyringa 
dissimilis, Tethyopsis columnifer, the branching Geodia ramodigitata, and the great cup- 
shaped Cydonium japonicum, Cydonium globostellifera (a well-marked species which 
ranges from Torres Strait to Ceylon), Placospongia melobesioides, and Placospongia 
carinata, Thrombus challengeri, and numerous Lithistids. 
The affinities of the fauna of this province with that of Brazil and the Caribbean are 
very remarkable : the genus Placospongia is confined to them, Thrombus challengeri is 
represented by sub-fossil spicules of a closely allied form {Thrombus kittoni) in Panama, 
Trihrachium schmidtii appears to represent Disyringa dissimilis ; among the Lithistida 
Neosiphonia superstes is represented by Neosiphonia schmidtii, Scleritoderma Jlabelli- 
formis by Scleritoderma packardi, and Siphonidium capitatum by Siphonidium ramosum. 
The explanation of this is probably not to be found in any assumed recent close 
