98 Mr. P. F. Bellamy on two Peruvian Mummies. 



inches. In making these measurements I have chosen the 

 skull of the elder mummy, because its form is not so exagge- 

 rated as in the younger, in which the bones, from the greater 

 projection of the occiput, are comparatively longer. 



It will also be found, that even if the circumference of the 

 two skulls be the same by measurement in a transverse direc- 

 tion over the vertex from one occipital condyle to the other, the 

 Peruvian through its long axis is 5| inches, whilst that of the 

 Caucasian is but 4 J inches. The position of the foramen mag- 

 num too is remarkable, for it will be found to be considerably 

 anterior to the centre of gravity ; thus, from the centre of the 

 condyle of the occipital bone to the alveoli of the front incisors, 

 the distance is but 3 inches, whilst from the same point to the 

 line described by the greatest posterior projection it is 3| 

 inches ; nor is the facial angle less remarkable : in one it does 

 not exceed 85°, and in the other it is as little as 82° ; being 

 in the former 5°, and in the latter 8° less than in the Cauca- 

 sian of the same age. 



Here I will venture to call the attention of the Section to 

 the formation of the occipital bone, for in each skull the same 

 peculiarity exists ; that is, in the addition of a fifth rudimen- 

 tary portion of the same figure, and occupying the same po- 

 sition in both, viz. between the occipital portion of the bone 

 commonly so called, and the parietal bones, but below the 

 lambdoidal suture ; in this particular differing essentially from 

 the adventitious os triquetrum sometimes found. In the 

 younger of the two individuals it is, like the other rudiments, 

 distinct and separate (PL IV. fig. 2.) ; whilst in the elder, in 

 which the ossific process is more advanced, the junction of it 

 with the occipital portion is nearly complete, the suture only 

 remaining open at either extremity for little more than an 

 inch, but traceable through its entire length. Does this exist 

 by a strange coincidence as an anomaly of structure, or is it 

 to be considered as a normal formation peculiar to this race 

 of beings ? 



It will be manifest from the general contour of these skulls 

 that they are allied to those in the Museum of the Col- 

 lege of Surgeons in London, denominated Titicacans. Those 

 adult skulls are very generally considered to be distorted by 

 the effects of pressure ; but in opposition to this opinion Dr. 

 Graves has stated*, that "a careful examination of them has 

 convinced him that their peculiar shape cannot be owing to 

 artificial pressure ;" and to corroborate this view, we may re- 

 mark that the peculiarities are as great in the child as in 

 the adult, and indeed more in the younger than in the elder 

 * Dublin Journal of Med. and Chem. Sciences, No. 15. 



