198 PROCEEDINGS OF COLUMBUS MEETING. 



mollusks have been found there, but of the fifteen species brought hack bynie this 

 past summer and identified by l>r. Win. H. Dall,* all have living representatives 

 in Bering sea. 



When the three constructive episodes were ended, then began a period of de- 

 struction and rearrangement of material about the margin of the island. Here the 

 waves converted the lavas ami tuffs into bowlders, pebbles and sand, and distrib- 

 uted them along the shores in characteristic forms; the ice crowded the coarser 

 material inland, forming ramparts invulnerable to the assaults of the sea ; over 

 this in turn the sand was scattered, and not only were the margins thus extended, 

 but the Lowlying lava tlows were built upon and the newly formed areas firmly 

 joined to the mainland. The winds caught up the sands and built them into dunes, 

 which continuously encroach upon the sea and which are made constant by the 

 long roots of the wild grasses that ever grow upward as more sand is added. To 

 these processes an due about one-fifth of the area of Saint Paul, and such topo- 

 graphic features as the lagoon, the ponds along the shores, and the lakes at North- 

 east point. This work of construction continues and will probably keep pace with 

 the destruction of the island. 



About 36 miles soi^heast of Saint Paul lies Saint George, an island a little smaller 

 than its companion and very different topographically ; hut few cones dot its sur- 

 face ; accessible shores are exceptional : and instead of lowlying sea margins, hold 

 precipitous bluffs from 300 to 900 feet high are the rule — the island stands like a 

 mesa on a watery plain. While the story of its formation is in the main that of 

 its neighbor, there is another factor involved, that of orographic movement. There 

 is a floor of dark vesicular basalt, but the point of the first outpour is not well 

 defined. From Oolakaiy.i. the name given to the remains of a vent near the middle 

 of the island and now over 900 feet high, came the hulk of the succeeding flows. 

 Indeed the extravasation from this center, aided perhaps by outflow from other 

 vents to the northeastward, built up the entire eastern half of the island. This 

 main vent also contributed a sheet to the westward, which was augmented by 

 material from a great cone on the northern shore. This cone has been more than 

 half eaten away by the sea and now forms High bluff, a perpendicular tuff cliff of 

 nearly 1.000 feet. 



* Dr. Dall's report is as follows: 



" Washington, D. <'.. November 13, 1891. 

 Iicar .All-. Stanley-Brown : 



The fossils fr Black Mutt', Saint Paul island, Bering sea, an-, so far as determinable, of recent 



species still living in the same region, though other collectors have obtained at the same Ideality 



specimens of extinct forms. Beside remains of an ophiuran starfish and the tube of a worm, like 



that made by Sabella, there are remains of fifteen species of mollusks below enumerated. The 



figures in brackets following the name indicate the number of times the species occurred in the 



collection, ami thus their relative abundance. 



* Buccinum tenue, Gray ? [3] * Lepton grande, Dall [■!] 



* Buccinum polare, Gray '.' [I] Cardium gra niandicum. Gmel. [18] 



* A dmete couthouyi, Say ? [1] .' * " islandicum, L. (decoratum, Grew.?) [15] 

 Natica clausa, B. and S. [4] Tellina (Angulus), -p. [1] 



Modiolnria nigra. Gray [In] * Macoma {sabtitlosn, Spgl. ?) [1] 



Nucula, s]>._ perhaps V. tenuis [1] Kennerlyia grandis, Dall [1] 



Leda. sp. [1] Sax 'cava arctica [11] 



* Yoldia limatula, Say [1] * Panopea, sp. '.' fragment, possibly a Saxicava. 



The species marked with an "* " have not been re pone. I from t hi- locality before. 



Yours very truly, 



Wm. II. Dai,l, 



Paleontologist, U. S. Geological Survey.''' 



