Cope.] -^^^ [March 4, 



is deducted, is not great, and is intermediate between that seen in Bala- 

 ena and Megaptera. The right premaxillary may he traced for six feet 

 two inches. Behind it a portion of tlie superficies of the cranium slopes 

 towards tlie position formerly occupied as a blow hole. 



The margin of the maxillary is horizontal, and rather thin. It becomes 

 thicker posteriorly where it has been crushed back on the lateral orbital 

 process of the frontal. Its acuminate extremity is seen lying on the 

 latter. 



The orbital process of the frontal is remarkably massive, and might at 

 first be taken for the squamosal. Its posterior margin is free to within a 

 foot of the probable position of the blow holes. This fact, in connection 

 with its deep jpostero-inferior concavity in cross section, is conclusive as 

 to its relations. The form is not horizontally expanded as in Megaptera, 

 nor attenuated as in Balsena, but has rather the proportions seen in Eein- 

 hardt's figure of the young of Balsena mysticetus. (Om Nordhvalen PI. 

 III.) That is, it has subparallel anterior and posterior sides; the extremity 

 a little widened by the production backwards of the posterior portion. 

 The anterior portion also somewhat, though less, protuberant. The 

 whole extremity truncate and remarkably thickened. Thus it is nineteen 

 inches long, the anterior tuberosity seventeen inches deep, tlie i:)osterior 

 twelve inches deep ; the inferior outline nearly straight. The orbital con- 

 cavity, which is continuous with the optic foramen, opens behind the pos- 

 terior tuberosity, and is defined exteriorly by the expanded posterior mar- 

 gin of the bone. Thus the great tuberosity which gives character to the 

 bone was above and in front of the eye. 



The portion of the mandible preserved presents marked characters. The 

 inner face is slightly concave, or jDlane, the external strongly convex. The 

 inferior edge is narrowed, and the superior scarcely less so ; the inner 

 face rounds a little to the former, and to a wide groove just below the lat- 

 ter. This groove is one inch wide near the middle of the ramus, and is 

 marked by a series of many small foramina. These are closer together in 

 the anterior, and regularly more widely spaced to the posterior portion.. 

 Thus anteriorly they are 3.5 inches apart ; posteriorly four inches sepa- 

 rates them, and near the extremity of the series, six inches. I failed to 

 find any foramina on the external face of the ramus. It is difficult, how- 

 ever, to believe that they are totally absent ; it may be that they 

 are confined to the anterior portion, which has not been preserved. 

 This peculiarity, if entirely established, marks the species as quite 

 distinct from any heretofore known from characters of the mandible. 

 The depth in this species, at the point where the foramina are foru- inches 

 apart, is fourteen inches. 



There are some other pieces apparently belonging to the cranium, whose 

 exact positions I cannot now assign. One of these looks like a segment of 

 ramus of the lower jaw, but the convergence of the superior and inferior 

 outlines is too great. One face is plane-concave, the other convex flat- 

 tened, with oblique superior and inferior faces, the latter the widest. 

 Depth of plane, ten inches; do. exterior flattened face, 7.75 inches. Depth 



