September 22, 1905.] 



SCIENCE. 



6io 



bars uniting with the slender premaxillary 

 processes. A striking feature is the large 

 parietal foramen opening directly into the 

 brain case, as above described. It is note- 

 worthy that the occiput or back part of the 

 skull has practically the same composition as 

 that of the carnivorous dinosaurs, namely : 



(1) supraoccipitals bounding the parietal 

 foramen posteriorly (this foramen is, how- 

 ever, absent in the carnivorous dinosaurs) ; 



(2) lateral parietal plates which hardly enter 

 into the top of the cranial roof except to 

 bound the parietal foramina at the sides; (3) 

 the squamosals forming together with the 

 paroccipital processes the infralateral portions 

 of the occiput; (4) occipital condyles com- 

 posed exclusively of the basioccipitals. 



Correlated with the muscular insertions for 

 the motions of the powerful neck we find two 

 very powerful processes extending down from 

 the basisphenoidal region, presenting a wide 

 contrast to the comparatively slender proc- 

 esses observed in Diplodocus. The quadrates 

 and pterygoids have substantially the same 

 shape as in Diplodocus; the other bones of 

 palate are not preserved. Of .the bones of 

 the jaw the dentaries, coronoids, articulars 

 and angulars are well preserved, as shown in 

 the drawing. The coronoids have a consider- 

 able upward extension, but nothing to com- 

 pare with that seen in the Predentata since 

 it is not necessary to provide for the inser- 

 tion of muscles of mastication. 



It is this skull which was mainly used in the 

 mounted skeleton of Brontosaurus in the mu- 

 seum; only the anterior part of the skull of 

 this animal being known. 



2. Mounted Skeleton of Brontosaurus. 



The mounting of Brontosaurus has occu- 

 pied the museum staff more or less contin- 

 uously since the discovery of the skeleton by 

 Mr. Granger and Mr. Grant, of the American 

 Museum expedition, in 189Y. In 1898 and 

 1899 the excavation was completed, and a 

 little more than two thirds of the entire skele- 

 ton was recovered. The chief missing parts 

 are the skull, the three anterior cervicals, the 

 fore limbs of both sides from the shoulder 

 down, the upper portions of the sacrum, the 



hind limb of one side, and the terminal portion 

 of the tail. The restoration of the skull is 

 largely conjectural from that of Morosaurus 

 above described, and the missing j)arts of the 

 limbs are restored from the famous specimen 

 in the Yale Museum, the type of Marsh's 

 Brontosaurus excelsus. The terminal portion 

 of the tail is completed from another individ- 

 ual in the American Museum of Natural His- 

 tory. 



The special features of the skeleton are its 

 large size, the absence of crushing of the 

 bones, and the completeness of the ribs. The 

 mounting represents not only prolonged work 

 of difficult restoration under the supervision 

 of the head preparator, Mr. Hermann, but very 

 careful anatomical studies, in which Messrs. 

 Granger, Matthew and Gidley materially as- 

 sisted the writer. Messrs. Granger and Mat- 

 thew especially made a complete restoration 

 of the muscles of the shoulder girdle and fore 

 limb prior to the placing of these elements, 

 which was an extremely difficult matter. The 

 manus represents the single-clawed condition, 

 resulting from comparison with the feet of 

 many Sauropoda. The chief measurements of 



the skeleton are : 



Ft. In. 

 Length over all, from head to tip of 



tail 66 8 



Length of vertebral column 64 4 



Length of neck 16 10 



Length of tail 31 4 



Length of longest rib 6 9 



Length of hind limb including foot. 10 7 



Length of fore limb including foot. 8 6 

 Depth of body from lower end of 

 pubis to top of posterior dorsal 



spine 8 7 



Length of head as restored 2 4 



It is interesting to compare these measure- 

 ments with those of a fully grown ' sulphur 

 bottom ' whale, carefully measured by Mr. F. 

 A. Lucas, and reproduced at the St. Louis Ex- 

 position. This animal, a male, measured 74 

 feet, 8 inches, from the notch of the flukes to 

 the tip of the nose. The approximate weight 

 of the bones was 17,920 pounds. The entire 

 animal was estimated at not far from 63 tons. 

 We observe that while the body of the whale 



