MR. GERRIT S. MILLER'S paper, “Some o'¦'o¦ hitherto unpublished photographs and measurements of the Blue Whale” (Proc. U.S. Nat. Mus., Vol. 66, pp. 1-4, Pis. i.-ix.) is a welcome contri bution to the literature of Cetacea. In spite of its predominating importance to modern whalers, the blue whale (BalcBnoptera musculus) is still imperfectly known, particularly with regard to cranial characters. Mr. Miller publishes specially good figures of the skull, the rostrum of which has not suffered from the warping which commonly occurs on drying. He informs us that the specimen (Washington Museum) was an adult male, 75 feet long, captured off New foundland in 1903; but it may be remarked that the free condition of the distal epiphyses of the radius, ind ulna figured in PL viii. is evidence that the animal had not completely passed the adolescent stage of Flower, and that in any case 75 feet is a small measure ment for a really adult blue whale. The digits shown in the same figure appear to be too straight, and the hand is probably a reconstruction of a disarticulated flipper, as indicated by the fact that the numbers of the phalanges are low as compared with other records. Mr. Miller makes no comparisons, and his facts must speak for themselves. With regard to the skull, the rostrum deserves special notice, its sides being parallel in its posterior half, then converging in a gentle curve to the tip;-in striking contrast with the triangular, straight-sided rostrum of the fin whale (B. physalus). The premaxillae are noticeably parallel behind, instead of being arched outwards. The postero - internal processes of the maxillae are long, the orbital plates of the frontals diminish greatly in diameter in passing outwards, and the nasals are stout and broad. The palatines have parallel sides, and in the side view the straight outer edge of the maxilla and the outline of the vertex are other features in which this skull differs from that of a fin whale. Excellent figures are given of the atlas, axis, sternum, pelvic bones and scapula, the last showing the restored cartilaginous parts. As bearing on the great variability of the bones in the larger Cetacea it may be noticed that the sternum differs conspicuously from those figured by True in 1904, as well as from that of the Longniddry whale described by Turner. The long series of measurements of bones will be valuable as material for comparison with southern blue whales, the identity or otherwise of which with the northern species it will be the special object of the Discovery expedition to investigate.