[a]380 220 Breadth of radius at distal end 84 ... 140 88 Length of ulna (incl. olecranon) 323 ... ... 241 Breadth of ulna at distal end 79 ... ... 71 Length of sternum 1,143 1,455 1,530 ... Breadth of first segment of sternum 325 375 495 ... Length of first rib (straight) 457 543 505 323 Length of fifth rib (straight) 991 ... ... ... Length of tenth rib (straight) 737 ... ... ... [a] Median. [b] Inferior. [c] Process aborted on one side. [d] Second. Genus HYPEROÖDON Lacépède. HYPEROÖDON AMPULLATUS (Forster). _Balæna ampullatus_ Forster, Kalm’s Linnean Travels, vol. 1, 1770, p. 18, footnote. _Balæna rostrata_ Müller, Zool. Dan. Prodrom., 1776, p. 7. _Hyperoödon butskopf_ Lacépède, Hist. Nat. des Cétacés, 1803-4, pp. XLIV and 319. _Hyperoödon rostratum_ Wesmael, Nouv. Mém. Acad. Roy. Bruxelles, vol. 12, 1840, pls. 1, 2. _Hyperoödon ampullatus_ Rhoads, Science, new ser., vol. 15, 1902, p. 756. The National Museum has one skeleton of this well-known species, somewhat imperfect, which is labeled as having been obtained on the coast of Norway, and was received about the year 1875. Its catalogue number is 14499. This skeleton is about 19 feet long and has the following vertebral formula: C. 7; Th. 9; L. 9; Ca. 19 (+1?) = 44 (or 45). Eight chevrons are attached to the caudal vertebræ, and at least two more were present originally. The fifth thoracic vertebra has no facet on the centrum for the head of the sixth rib, but the latter articulates with a small facet on the side of the centrum of the sixth thoracic vertebra. The seventh thoracic has a well-developed transverse process on the side of the centrum. The ninth rib is shorter and more slender than the others. None of the transverse processes of the caudal vertebræ are perforated by foramina. These processes end on the eighth caudal, and the neural spines on the tenth caudal. The free ends of the neural spines of the thoracic and lumbar vertebræ are all more or less rounded. The pectoral limbs are incomplete. So far as I am aware, only three examples of _Hyperoödon_ have been taken on the coasts of the United States, as mentioned in the list on page 2. The skeleton of one of these (from North Dennis, Massachusetts) is in the Museum of Comparative Zoology, Cambridge, Massachusetts, and the skull of the second (from Newport, Rhode Island), which was a female, is in the Academy of Natural Sciences of Philadelphia.[62] This skull is represented in Pl. 32, fig. 3. LIST OF SPECIES OF EXISTING ZIPHIOID WHALES.