“The glenoid process is margined by an angular prominence, the rudiment of the coracoid, precisely as in the _M. brasiliensis_. The diapophysis of the atlas is a flat vertical plate, extending from opposite the base of the _foramen dentatum_ to opposite the widest point of the spinal canal; inferior posterior outline of the atlas broad, slightly concave mesially. The mandible is peculiar in the strong angular process, which extends from behind, round the side, projecting as far as the condyle, and separated from it by a deep groove. The third and fourth cervicals are united by the neural arch. The first rib is very broad at the extremity; length 37 inches, width at end 8·22 inches. The orbital processes of the frontal bone are not contracted at the extremities as in _M. longimana_, but are more as in _Balænopteræ_; entire width over and within edge of orbit 15½ in.; length to vertical plate of maxillary 31 inches. The baleen measures 2 feet in length, is black, with three rows of coarse bristles. Its base is one curve; its length is spirally twisted. The species is probably one of the largest of the _Balænidæ_.”—_Cope_, _Proc. Acad. Nat. Sci. Philad._ 1868, p. 194. 7. Megaptera versabilis. Megaptera versabilis, _Cope_, _Pr. Acad. Nat. Sci. Phil._ 1869, p. 17, figs. 5 & 6. Inhab. North Pacific, Californian coast. 2. POESCOPIA. Poescopia, _Gray_, _l. c._ p. 113; _Synops. Whales & Dolph._ p. 2. Bladebone with small coracoid process. Body of cervical vertebræ nearly square. 1. Poescopia Lalandii. B.M. Poescopia Lalandii, _Gray_, _l. c._ pp. 126 (fig. 19, p. 125), 373; _Synops. Whales & Dolph._ p. 2, tab. 33. f. 3, 4 (vertebræ, from _Cuvier_). Inhab. Cape of Good Hope. Skeleton, Mus. Paris. 3. ESCHRICHTIUS. Eschrichtius, _Gray_, _l. c._ pp. 113, 131; _Synops. Whales & Dolph._ p. 2; _Lilljeborg_, _N. Acta Upsal._ vi. p. 12, 1867. Bladebone with large coracoid process. Body of cervical vertebræ separate, small, roundish-oblong. The neural canal very broad and high. 1. Eschrichtius robustus. B.M. Eschrichtius robustus, _Gray_, _l. c._ pp. 133 (fig.), 373; _Synops. Whales & Dolph._ p. 2; _Lilljeborg_, _N. Acta Upsal._ 1867, vi. p. 16, t. 1-8; _Cope_, _Proc. Acad. Nat. Sci. Philad._ 1865, p. 4. Inhab. North Sea; coast of Devonshire, Sweden; Atlantic. “The _Eschrichtius robustus_ is admitted on the evidence of a ramus of the under jaw in the Museum, Rutger’s College, which is of peculiar form, and closely resembles the figure given by Lilljeborg of that portion of this rare species.”—_Cope_, _Proc. Acad. Nat. Sc. Philad._ 1868, p. 194. Family 4. PHYSALIDÆ. _Finner Whales._ Physalina, _Gray_, _l. c._ pp. 114, 134. Physalinidæ, _Gray_, _Synops. Whales & Dolph._ p. 2.