262 Proceedings of the Boyal Physical Society. 



the palate bone, is §| inches ; from this point of the palate 

 bone to the posterior edge of the basi-sphenoid, the distance 

 is 2} inches ; the length from the incisive edge of the pre- 

 maxillaries to the coalesced basi-sphenoid and basi-occipital 

 is, therefore, 11 inches, or half an inch less than in the skull 

 from Old Calabar ; and from the anterior border of the pre- 

 maxillary bones to the anterior edge of the foramen magnum, 

 the total length at the base of the Honduras skull is 13 

 inches. The pterygoid bones are 2 J inches in length, with 

 a smooth outer ridge behind, and another inner ridge, which 

 terminates in a short obtuse hamular process. They coalesce 

 with the pterygoid processes of the palate bone, which are 

 large, twisted backwards and outwards, and cover, without 

 concealing, the posterior aveoli. 



The foramen magnum is oval transversely, 2 inches from 

 side to side, and an inch and a half from above downwards. 

 The occipital condyles are l T \th inch in length, and l T 2 0 -th 

 inch in breadth, and approximate to each other in front. 

 The paroccipital wings at the posterior roots of the condyles 

 expand upwards, inwards, and outwards, in a broad semi- 

 lunar form, convex above and concave below, where they 

 join the less prominently developed mastoids. 



From the posterior edge of the foramen magnum, along 

 the perpendicular occipital spine, to the large straight trans- 

 verse occipital ridge, the distance is 2 T 8 o-th inches; and from 

 the middle of the occipital crest to the anterior incisive 

 margin of the premaxillary bones, following the curve of 

 the coronal aspect, the length of the skull is 15 inches. 

 There is a deep hollow space extending along the middle of 

 the upper convex aspect of the skull, which is formed by a 

 strongly developed longitudinal ridge on each side. These 

 lateral ridges commence at the posterior inferior parietal 

 angle, where they are 3 inches apart ; the parietal portion of 

 the ridges gradually approximate as they advance forwards, 

 until, at the coronal suture, they are only an inch apart. 

 The ridges again diverge, increase in size, and form two 

 anterior superior parietal processes, which extend forwards 

 for about 2 inches in a notch in the frontal bone. They 

 then advance forwards and outwards as frontal ridges, nar- 



