MORPHOLOGICAL REVISION 



US 



and behind by bars of bone. At about 30 mm. from the middle line, this 

 groove turns at an acute angle forward nearly parallel to the median axis 

 of the skull, to terminate at the outer end of the pterygoids and leading 

 into the temporal vacuity. The bone containing this groove shows at its 

 inner extremity a distinct suture separating it from the occipital and basi- 

 sphenoid. It is doubtless, in part at least, the paroccipital. 



"The pterygoid, from the basisphenoid articulation, turns transversely 

 outward as a vertical plate, ending in a sutural articulation, just back of the 

 orbit, with the anterior end of the bony ridge bounding what I believe to 

 be the otic groove. The plate does not seem to reach quite to the roof of the 

 skull in its middle part. The under margin of this plate is widened a little 

 anteroposteriorly externally. Its outer extremity is lost, but it doubtless 

 unites with the palatines at the outer side of the palatal surface, and prob- 

 ably sends back a posterior process at the sides to connect with a broken 

 extremity of a flat bone on the inner side of the quadrate. The attachment 

 of this bone, or of a separate transverse bone, is shown by a broken edge 

 turned downward a little below the plane of the palatines to abut slightly 

 against the upper inner margin of the mandible. There is no indication of 

 a median parasphenoid prolongation in front of the basisphenoid, but a 

 broken surface of a bone forming the brain case for the cerebrum, may per- 

 haps represent what is left of the parasphenoid, which must in this case be 

 far above the plane of the palatines and closely applied to the under side of 

 the brain and its rhinencephalic anterior prolongation. The palatines, or 

 the combined palatines and pterygoids, form a narrow horizontal shelf along 

 each maxilla. The inner part of this shelf is thickened, so that its median 

 border forms nearly a flat surface directed inward and downward, and 

 separated by a depression or groove from the outer palatinal surface. Prob- 

 ably this portion represents the anterior prolongation of the pterygoids, 

 but I can distinguish no trace of a suture between the two portions. The 

 palatal shelf of the left side was crushed against the opposite side in the 

 specimen, lying quite in contact nearly as far back as the orbits. There 

 could not have been any median parasphenoid between the two parts, the 

 angle anteriorly being acute and the palatines or vomers meeting and com- 

 ing closely in contact anteriorly. The internal nares are oval vacuities 

 situated nearly below the anterior part of the lateral facial vacuities. Just 

 in front of the opening on each side and close to the margin of the mandible, 

 as articulated, there is a large tooth, doubtless situated upon the vomer. 

 There are four large teeth upon the palatines, also attached so that they 

 come closely in contact with the inner side of the mandible in the closed 

 mouth. These teeth are in two pairs. The first pair, of which the anterior 

 one is the smaller, are situated a little in front of the orbit, the apex of the 

 larger tooth reaching nearly to the lower border of the mandible. It has 

 a length of 22 mm., with a width of 12 mm. at its base. The posterior pair, 

 of nearly equal length, measuring about 12 mm. each, are also closely applied 

 to the inner side of the mandible a little back of the middle of the orbit. 



" Teeth: There are twenty-five or twenty-six teeth in each of the upper 

 series, and about the same number in each mandible. Six of these, of rather 

 small size, are attached to the premaxilla in front of the lateral narial 

 opening. The longest measures 8 mm. The largest of the maxillary teeth 

 are situated back of the middle of the narial vacuity, two of them measuring 

 14 and 15 mm. in length, by 5 mm. in diameter at their base. 



