Emerton.] 342 [March 2, 



General Meeting, March 2, 1887. 

 The President, Mr. S. H. Scudder, in the chair. 



The President announced that he should decline reelection at 

 the next annual meeting, when he will have completed seven years 

 of service. He suggested, that it would be for the interest of the 

 Society to make the office an annual one, and he hoped that the 

 members would consider this question carefully. 



Mr. L. P. Nash was elected an associate member. 



The President then introduced Mr. C. D. Walcott of the U. S. 

 Geological Survey, who gave an account of a" Trip through the 

 Grand Canon of the Colorado." Mr. Walcott illustrated his re- 

 marks by showing many lantern pictures, presenting to the Society 

 a continuous view of the geology of the Grand Canon, which he has 

 done so much in elucidating. • 



Mr. J. H. Emerton described the restoration of the skeleton of 

 Dinoceras mirabile. 



Soon after the publication of Prof. O. C. Marsh's monograph of the 

 Dinocerata the speaker began a restoration of the skeleton of Dinoceras 

 mirabile which has just been finished and copies mounted in the Yale Col- 

 lege Museum and the Museum of Comparative Zoology in Cambridge. 



The collection of Professor Marsh contains portions of nearly every 

 bone in the skeleton of Dinoceras, but these belong to many individuals 

 of all sizes and proportions, so that few parts of the restoration could be 

 cast directly from the bones, the rest having been modelled in clay. 



The size of this restoration was determined by the bones of Marsh's 

 type specimen of D. mirabile. These include a nearly complete skull 

 only slightly distorted, the pelvis, lumbar vertebrae, one vertebra of the 

 neck and two ribs, plaster casts of all of which have been made and dis- 

 tributed to various museums. 



No complete vertebral column has been found, so that the number of 

 vertebrae is uncertain, and the number made is the same as found in the 

 horse and tapir and in the elephant to which the Dinoceras appears 

 nearly related. There are several sets of vertebrae in the collection 

 from different parts of the column from which the form of all can be cop- 

 ied, except those in the middle of the back which are modelled from a 

 few fragments. The lateral processes of the lumbar vertebrae have been 

 restored in shape following the same bones in the hippopotamus. The 

 posterior half of the sacrum of the type of D. mirabile is wanting and 

 has been restored from other specimens. 



There are several vertebrae from different parts of the tail, so that the 

 shape is tolerably certain, though the number of vertebrae is unknown. 



There are very few complete ribs in the collection, and excepting the 



