232 



MEMOIRS OP THE NATIONAL ACADEMY OF SCIENCES. 



Auoutchine gives in another table a list of 12 series of diverse races, in which there are pteria 

 less than 3""" in percentages, ranging from 0.5 to 8.2 (Chinese). Since the Peruvians do not appear 

 on this table, we presume their percentage is zero. Such is the case with the Cibolaus, but, as 

 before stated, we found one of these small pteria in a Saladoan skull. 



f, 42. INCA BONE AND KINDRED FORMATIONS. CIBOLA. 



As we have not secured illustrations to show for this series the anomalies involving the 

 superior angles of the vertical portions of the occipital bone, we have prepsired a list of these 

 anomalies, 12 in all, with a detailed description of each case. 



List. — H. 203 : In the left limb of the lambdoid suture there are Wormian bones, one of which 

 sends a process across the apex. 



H. 20G : A typical os apicis 32™" high by 51'"™ broad. It has Wormian bones at its lower 

 angles. 



H. 207 : A very curious multiple apicial bone reaching to within 3"'™ of the obeUon. It consists 

 of nine principal and many smaller portions. The whole group is 43™™ high and 51™™ wide, and 

 might by some be considered an os Incce. The bone forming the apex is 21'""' by 17™™. 



H. 210: Pine tortuous Wormian bones in both limbs of the lambdoid suture. There is one 

 of this set at the apex, a small irregular ossicle, which ndght be regarded as an os sagittalc. 



H. 212: A large compound bone at the apex, mostly to the right of the median line. The 

 lower part of it, about 40™™ by 32"'™, is partly coossifled to the rest of the occipital. The upper 

 part, about 22"'™ by 9™™, forms a small apicial bone. A few Wormian bones of small size 

 complicate the lambdoid. 



H. 213: A row of medium-sized Wormian bones in each ILmb of the lambdoid suture; one of 

 these bones is ou each' side of the apex; 12™™ above the apex is an os sagittale 18'"'" by 9'"™. 



n. 218: An apical bone in two parts slightly coossifled. The total size is 25'"™ high and 

 47™™ wide. 



H. 223: A row of medium-sized Wormian bones, all of remarkably simple outline, in each 

 limb of the lambdoid suture. One of these bones situated at the apex measures 14™™ by 16™™. 



H. 227 : A large typical Inca bone 40™™ high and 73"'"' wide. Above it is a small bone 7™™ 

 by ] 0™'", which may be regarded as an os sagittale. 



n. 231: A triangular os apicis, 27™™ by 53™™. 



H. 232: A row of long, very irregular Wormian bones occupies the lambdoid suture throughout 

 from the left asterion almost to the right; one of these bones, .situated in the median line, is about 

 gmm ^y i4mm^ ^ud may be considered an apicial bone. 



H. 233: A row of Wormian bones occupies the upper half of the right limb of the lambdoid 

 suture; one of these, 13™™ by 14™™, touches the median line at the apex. 



Prom the above list we learn that there are in this series the following anomalies : 1 typical 

 Inca bone, H. 227; 5 typical apicial bones, Nos. H. 206, H. 207, H. 212, H. 218, H. 231; C doubtful 

 apicial bones, Nos. H. 203, H. 210, H. 213, H. 223, H. 232, H. 233, or 11 apicial bones of both 

 classes — 12 anomalies in aU. The above numbers give us, in a series of 35, the following percent- 

 ages: luca bone, 2.85 per cent; true apicial bones, 14.28 per cent; doubtful apicial bones, 17.14 

 per cent; both classes of apicial bones, 31.42 per cent; total of all anomalies 34.28 per cent. From 

 these percentages, from those given in paragraph 18, and from percentages obtained from our 

 own collection we havQ prepared the following table: 



Table W. — Frequency of Inca bone in various peoples. 



