O. C. Marsh—Sternum tn Dinosaurian Reptiles. 395 
System Trimetric with hemihedral habit. 
Observed planes + % | 111 | | 100] | 110] | 011]? 
In the following table the crystallographic ratios are com- 
pared with those of the acid tartrates of rubidium, cesium and 
potassium, formerly measured by us, and which have the same 
general form and hemihedral habit. 
Vertical. Macro.  Brachy. 
61 1 0°694 
Acid tartrate of czesium 0°6 
Acid tartrate of rubidium 0°695 1 0°726 
Acid tartrate of potassium 0°737 1 0-711 
Silver emetic 0°412 1 0°721 
Art. LV.—The Sternum in Dinosaurian Reptiles ; by Professor 
O. C. Marse. (With plate XVIII). 
e. 
e Yale Museum has recently received a nearly com- 
plete skeleton of Brontosaurus excelsus, one 0 the largest 
known Dinosaurs. This huge skeleton lay nearly in the posi- 
In adult anim 
anterior end of each bone is considerably thickened, and there 
18 a distinet facet for union with the coracoid. The posterior 
end is thin, and irregular. These bones are shown in position 
* Geology of Oxford, p. 268, 1871. 
+ Palzontographical Society, p. 31, 1875, 
