22 ABT. 3. — B. KOTü : 



sandstone and a strong bed of puiniee, capped with a sheet of 

 lava-flow. The eastern sister island, Takeno-shima, has tlie 

 same topography (100 m.) and the same lithologie elements. 

 KuEO-SHiMA, lying 17 miles west of the former, was seen by 

 him, however, only from a distance, and we know nothing about 

 its rocks and eruptions. Probably it is of the same type as the two 

 preceding ones. Kuchixo-Eeabu (Fig. 2 ; Fig. 1 K.^ is also a clifF- 

 bound flat island, 150 in. high, and geologically and topographi- 

 caUy an exact copy of Iwô-jima, above referred to. These 

 four islands were later crowned with recent volcanoes. 

 CoxcLTJsioN From the similarity in the geology and topography of 

 adjoining lands and the insular group in question, we can picture 

 in our mind the region to have been once an extensive plateau - 

 land, which was later shattered, contemporaneous with the creation 

 of Kagoshima Bay, Oshima Strait, and the intervening seas between 

 the shattered islands. If the writer is not mistaken in Jtis suggestion, 

 the îcliole group of the ahore-mentioned islands, together with Yahu, 

 Tankga-shima, Mage, and Kiichino-Erahu, must have once formed an 

 integral j}art^^ of ancient southern Ki/ilshit. 



C) The Foundation of Sakura-jima. — The question as to the 

 immediate foundation of any volcano cannot usually 1)0 easily ans- 

 wered. In a case hke the present, wliich is that of an isolated insular 



1) See the area clotted with islands in Sketch Map of southern Kyushu in Fig. 2, and also 

 the region enclosed by the 500-meter isobathe ofE southern Kyûshû including K-i (Kuchino-Erabu 

 Island) and I (lAvô-jima) in Fig. 1. 



The conclusion arrived at here is also confirmed from the Zoogeographie point. From the 

 study of the Japanese termites, of which now twelve in number are known, I'rof. S. Watasé 

 says that the two islands of Yaloi-shima and Tanéga-shima form the southwestern outpost of the 

 Pala-arctic section of the Japanese Empire, while the island of (Jshima (Anami-Ûshima) marks off 

 the extreme northeastern boundary of the Oriental Kegion. See Figs. 1 and 2. The southern border 

 of the shattered region of southern Kyûshû, above referred to, is therefore an important faunastic 

 divisional line of old geologic date from a termitologic point. See X. Holmgren, ' Die Termiten 

 Japans.' Annotntiones Zoolorjica; Japonenses, Tôlcyû, ^'ol. VIII. Part I., 1912, footnote p. 10!). 



