SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 21 
promises to throw hght upon the problem of the ancestry of 
our modern baleen whales. 
The Find. 
The find consists of two fragments of a skull evidently from 
the postrior middle portion of the nose part, and of parts of 
the low lower jaws. The fragments consist of the maxillaries, 
pre-maxillaries and nasal bones. The specimen in being laid 
down was slightly distorted, but the bones are in a perfect 
state of petrifoetion. 
Judging from the size of the fragments this animal when 
living was approximately 25 feet long, and by the contour of 
the lines definitely shown the skull was more elongated than 
that of the hving whale. The maxillaries curve strongly out- 
ward posteriorly; and the nasal bone thins rapidly forward 
suggesting that it was very much shorter than the mawillaries 
and premaxillaries or that this is a specimen of a young animal, 
hence ossification being not complete. 
The baleen surfaces are smooth and evenly curved, and a 
large blood-vessel path is found here. All of these points are 
dupleated in our living baleen whales. 
The fragment of the lower jaw shows no signs of gingival 
dental canal or foramena, but the ramus shows a large dental 
canal near the center. Pi. IJ, Fig. 2-3. A foramen for a blood 
vessel appears, but no Meckehan fissure is present. The ra- 
mus is shehtly curved inward and upward similating the mod- 
ern whale’s jaw. 
Thus the absence of teeth, and no traces of a dental grove, 
the sheht curvature of the ramus, a centrally located dental 
canal, the elongated nasal portion, and the well-defined baleen 
surface identify this find as being an ancestral type of our 
modern baleen whales. I have little doubt that this specimen 
will prove upon further investigation to be very nearly akin 
to the whales that now inhabit the waters of our coast, and 
give to us a new species if not a new genus. 
It is interesting then to note that at no distant day, geologi- 
‘ally speaking, the hills we have at present were in the sea, the 
Hinty sand-stones were being laid down while the predecessors 
of our whales sported over them and in turn died and were 
buried. Disintegration began and particle by particle the 
living substances gave place to infiltrating silicious material 
and the petrified form was made. It now awaited the oro 
eraphic movements of our coast to land it high and dry and 
subsequent erosion to reveal its presence and enable us to have 
an idea of its interesting past. 
