232 



MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



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

 less than 3 mm 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 Cibolans, but, as 

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



$ 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 prepared a li.st 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. 206 : A typical os apicis 32 mm high by 51 mm broad. It has Wormian bones at its lower 

 angles. 



H. 207 : A very curious multiple apicial bone reaching to within 3 mm of the obelion. It consists 

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

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



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

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



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

 lower part of it, about 40 nim by 32 U1D1 , is partly coossified to the rest of the occipital. Tin- upper 

 part, about 22 mm by 9 mm , 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 Iknb of the lambdoid suture; one of 

 these bones is on each side of the apex; 12 nim above tlie apex is an os sagittali' IS"" 11 by 9 11 "". 



H. 218: An apical bone in two parts slightly coossified. The total size is 25""" high and 



47mm 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 nim by 10 nim . 



H. 227 : A large typical Inca bone 46 mm high and 73"" 11 wide. Above it is a small bone 7 mm 

 by 10, which may be regarded as an os sagittate. 



H. 231: A triangular os apicis, 27 mm by 53 mm . 



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 

 gmin by i4mm^ an( j 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 mm by 14""", touches the median line at the apex. 



From 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; 6 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 all. The above numbers give us, in a series of 35, the following percent- 

 ages: Inca 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 have prepared the following table: 



% TABLE W. Frequency of Inca bone in various peoples. 



