638 PEOF H. G. SEELEY ON THE SKTILL OP 



dinal parallel grooves, which, however, cross them at a slight angle, 

 heing prolonged a little further forward, and down into the boat- 

 shaped depression in the head formed posteriorly by the nasal, frontal, 

 and postfrontal bones. Anterior to these rounded ridges the bones 

 are somewhat flattened above, but rounded from side to side. The 

 median suture dividing them is about 13 inches long. The width 

 of the nasal bones measured transversely between the nares is Sc- 

 inches; the transverse width of the skull in the line of their 

 posterior borders is about 8| inches, while the transverse width of 

 the skull at their anterior termination is about 4J inches. 



The premammary bones (pm), as already remarked, are imperfect 

 anteriorly; they are preserved for a length of over 11 inches, but 

 the part where they meet superiorly in the middle line, undivided 

 by the nasal bones, is only about 3 inches long. The sides are a 

 little flattened, but they round convexly above, and the median 

 suture is a little impressed, so that the limits of the bones are 

 distinctly marked by a groove, unlike the anterior portion of the 

 nasal bones. As the premaxillary bones extend backward they 

 narrow a little from being overlapped on the alveolar border by 

 the maxillary bones (m) : their upper and under sutures are com- 

 paratively straight and subparallel. Each bone is forked at its 

 posterior termination by receiving in a notch the anterior part of the 

 long ovate anterior nasal aperture. It forms more than a third of 

 the wall of this cavity on the right side, and on the left side is pro- 

 longed along nearly the whole upper margin, so as almost to exclude 

 the nasal bone from the anterior nares. The lateral surface of the pre- 

 maxillary is somewhat roughened with vascular perforations in its 

 hinder part. The only other bones which enter into the upper 

 surface of the skuU are the postfrontal and squamosal, which may 

 be more conveniently described in noticing its lateral characters 



(fig- 2). 



The anterior nares (iV) vary a little in their distances from the 

 back of the head; measuring from the hinder border of the squa- 

 mosal bone to the posterior border of the nasal aperture, the distance 

 is about 14| inches. The length of the nostril is 4^ inches, and its 

 depth in the posterior third IJ inch. Its distance from the end 

 of the snout, as preserved, is rather less than 9 inches. The posterior 

 border of the cavity is rounded and formed by the nasal bone above 

 and the lachrymal bone behind and below. The middle of the base, 

 which is straighter than the upper border, is formed by the max- 

 illary bone ; and anteriorly the nostril terminates, as already indi- 

 cated, in the premaxillary in a sharp angular notch. 



The maxillary hone (m) is much longer on the left side of the head 

 than on the right side, though the alveolar border is better preserved 

 on the right side. Its length on the left side is about twelve 

 inches ; on the other side it is much less. I am not sure from 

 the condition of the palate how many teeth it contains ; but as it ex- 

 tends forward almost to within 5 inches of the truncated end of the 

 snout, I have no doubt that it contained several, since the alveoli 

 extend along fully 8^ inches of the palatal border as preserved, 



