REPORT ON THE DEPARTMENT OF LITHOLOGY AND PHYSICAL GEOL- 

 OGY IN THE U. S. NATIONAL MUSEUM, 1885. 



By George P. Merrill, Acting Curator. 



The total uumber of accessions duriug this time as shown by the de- 

 partment catalogue has been four hundred and eighty-five. As these 

 are described in Part IV of this report, mention will here be made only 

 of a few of the most important. 

 Sealy, Capt. M. A. Collection of rocks from Sali wick Lake and Kowak 



Eiver, Alaska. (Ace. 15278.) 

 3fason, 0. F. Two specimens fulgurites, from Sumter, S. 0. (Ace. 15994 



and 16052.) 

 Ophite Marhle Company^ New Yorlc. A large ophite marble mantel and 



wainscoting. (Ace. 16013.) 

 Stoney. Lieut. G. M. A collection of eruptive rocks (hornblende ande- 

 site) from the volcano on Bogosloif Island ; also collection of rocks 

 from Saliwick Lake and Kowak Eiver, Alaska. (Ace. 15688.) 

 U. S. Geological Survey. A collection numbering some 125 and specimen 

 rocks, from the Lower Silurian formations of Tennessee. Received 

 from G. K. Gilbert. 

 U. 8. Geological Survey. A collection of tufas and eruptive rocks, from 

 Nevada, California, Oregon, and Utah. Received from I. C. Rus- 

 sell. (Ace. 15872.) 

 The fulgurite tubes received from Mr. 0. F. Mason, of Sumter, S. C, 

 form a valuable addition to our already fine collection of these pe- 

 culiar objects. They present the usual form of very irregular cor- 

 rugated tubes with glassy interiors, but are remarkably thick and 

 strong. They are reported by Mr. Mason as beiug found sooie 20 feet 

 below the surface while digging a well. The large ophite mantel and 

 wainscoting, the gift of the Ophite Marble Company, of New York, 

 although a manufactured article and possibly open to objection in that 

 it i^artakes of the nature of an advertisement, is nevertheless of great 

 value as showing the wide variations in texture and structural peculi- 

 arities common to this stone, and also the effective manner in wliich 

 these points can be brought out by judicious cutting. 



The collections brought in by Capt. M. A . Healy and Lieut. G. M. Stoney 

 from Saliwick Lakes and the Kowak Eiver, Alaska, were not only of inter- 



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