Geology. 



421 



pond in form with the corresponding deciduous teeth, but are of larger 

 size. Finally, a portion of the lower jaw of an aged specimen of Dicho- 

 don, in the British Museum, showing the effects of attrition on the last 

 molar tooth, was described, and the results of this additional evidence 

 confirmed the conclusions of the author as to the generic distinction of 

 the Dichodon. 



8. On a Range of Volcanic Islets to the Southeast of Japan ; by 

 Mr. A. G. Findlay, (Proc. Brit. Assoc., August, 1856 ; Ath., No. 

 1503.) — The recent importance of our commercial relations with Japan, 

 consequent upon the opening of the ports of Nagasaki and Hakodadi to 

 our merchants, and the increasing commerce now developing itself between 

 Eastern Asia and Northwest America, has rendered the great ocean-high- 

 way between Nippon and the Bonin Islands of great interest. The dan- 

 gers of this region to the seaman are much increased by the rapid Japan- 

 ese current, first shown by the author in 1850 to run from east to west 

 across the North Pacific Ocean, in an analogous course to the Atlantic 

 Gulf Stream. This mighty stream running to the ENE, through the 

 space under consideration, has given rise to the very complicated nature 

 of the so-believed new discoveries. Above thirty of these announcements 

 being, by investigation, reduced to five or six rocky islets of very singular 

 character. The islands nearest to Japan, the Broken Ids, Falsisyo, the 

 Japanese penal colony, and South Island, were shown to be in some cases 

 defectively represented. The Redfield Rocks are those discovered by 

 Broughton, and corrected by Capt. Donnell in 1850, and therefore not a 

 discovery by the United States Japan Expedition in 1854. The islands 

 south of this are, perhaps, Tibbit Island of 1844, then an island or reef 

 of pointed rocks, discovered by Coffin in 1825, afterwards announced as 

 new by Captain Jurien-Lagraviere in May, 1850 ; again announced as 

 new by Captain Rogers in 1851 ; again in 1852 by Captain Dresher of 

 the Walter, and again in 1856 by Capt. Grove, each person believing that 

 he had discovered a new island. Others similar were also cited. The 

 next group, perhaps, is about eight miles to the south of the last, or lat. 

 31° 53' N., long. 139° 59' E., was discovered in the Dutch corvette, the 

 Koerier, August 24, 1849, and are of a very dangerous character. Jean- 

 nette Island, twenty-three miles further south, is doubtful. Smith Island, 

 in lat. 31° 12', long. 139° 55', discovered by Capt. Smith of the Heber, 

 March, 1846, is a most singular needle-rock, springing from unfathoma- 

 ble depths to 300 feet high and not more than 250 feet diameter at the 

 base. It has been seen by others. Ponafidin Island of the Russians lies 

 next, to the south. St. Peter's or Black Rock, first seen in 1821, and 

 again in 1853, is a wonderful column of basalt or volcanic glass, 200 feet 

 high, parallel and quite perpendicular sides, not more than 150 feet in di- 

 ameter, aitd like a bottle in appearance. It is in lat. 29° 42', long. 140° 

 15'. The volcanic nature of these remarkable rocks lying near the me- 

 ridian of 140° E. indicates a continuation of those immense volcanic 

 ranges which pass along the Kurile Islands, throughout Nippon, the great 

 Japanese island, and thence to the well-known range of spiracles in the 

 Ladrone Islands. At the northern end of this range is the well-known 

 Mount Fusi, 10,000 or 12,000 feet in height, now quiescent. To the 

 south of this volcano is Simoda, — a port between the two capitals of Ja- 



