no. 1808. RECENT AFRICA X CRINOIDS— CLARK. 13 



Southeast coast. — The southeastern coast of Africa is faunally the 

 richest section of the continent, supporting twenty-two species dis- 

 tributed among eighteen genera, of which latter eleven do not occur 

 farther north. All of the genera are widely spread throughout the 

 Indo-Pacific-Japanese region, but sixteen of the twenty-two species 

 are confined to southeastern Africa, only six occurring in Ceylon and 

 eastward. The only four species of the deeper water yet known 

 belong to characteristically East Indian genera. 



The affinities of this district are obviously with Ceylon and the 

 region to the eastward of that island rather than with the coasts of 

 the Arabian Sea, and the modern crinoid fauna evidently worked 

 southwestward along the line now indicated by the Maldive, Chagos, 

 and Cargados islands to what is now Mauritius, Madagascar, and 

 southeast Africa. 



The following genera are common to southeast Africa and Ceylon 

 (or the Bay of Bengal), but do not occur on the shores of the Arabian 

 Sea north of Ceylon or north of British East Africa: 



Gomatella. Decametra. 



Capillaster. Oligometra. 



Comissia. Crotdlometra. 



Bennettia group of Comanthus. Gosmiometra. 



Amphimetra. Pachylometra. 



Cenometra. Perometra. 



The same is, so far as we know, true of the following species: 



Gomatella ma'culata. Stephanometra indica. 



Capillaster multiradiata. Dichrometra jlagellata. 



Oligometra serripinna. 

 As the south European-northwest African-Antillean division offers 

 some striking points of similarity to the attenuated western extremity 

 of the Indo-Pacific-Japanese region, as seen in southeast Africa, we 

 are justified in supposing that it was originally derived from it by 

 passage across what is now central Africa; in other words, that the 

 genera characterizing it have moved outward from the East Indian 

 region, first southwestward to southeast Africa and then northeast- 

 ward to their present habitat. 



The area from Mombasa southward to Cape Colony, and including 

 Madagascar, the Seychelles, Reunion, and Mauritius, and the other 

 islands as far as the Chagos group may be conveniently known as the 

 Southeast African faunal division of the Indo-Pacific-Japanese region. 

 Along the coasts of Cape Colony and Natal occurs a comasterid 

 {Comanthus wahlbergii) found nowhere else, but closely related to 

 Comanthus trichoptera of southern Australia. Although it is asso- 

 ciated with tropical forms, and although there are no representatives 

 there of the other south Australian species, we must recognize the 

 fact that the Cape subdivision is not quite the same faunally as the 



