62 THE DESCENT OF MAN 



mammals, normally consists of two portions. TMs is its 

 condition in tlie human foetus when two months old; and, 

 through arrested development, it sometimes remains thus in 

 man when adult, more especially in the lower prognathous 

 races. Hence Canestrini concludes that some ancient pro- 

 genitor of man must have had this bone normally divided 

 into two portions, which afterward became fused together. 

 In man the frontal bone consists of a single piece, but in the 

 embryo, and in children, and in almost all the lower mam- 

 mals, it consists of two pieces separated by a distinct suture. 

 This suture occasionally persists more or less distinctly in 

 man after maturity; and more freqxiently in ancient than 

 in recent crania, especially, as Canestrini has observed, in 

 " those exhumed from the Drift, and belonging to the brachy- 

 cephalic type. Here again he comes to the same conclusion 

 as in the analogous case of the malar bones. In this, and 

 other instances presently to be given, the cause of ancient 

 races approaching the lower animals in certain characters 

 more frequently than do the modern races, appears to be 

 that the latter stand at a somewhat greater distance in the 

 long line of descent from their early semi- human progenitors. 

 Various other anomalies in man, more or less analogous 

 to the foregoing, have been advanced by different authors, 

 as cases of reversion ; but these seem not a little doubtful, 

 for we have to descend extremely low in the mammalian 

 series before we find such structures normally present." 



Canestrini gives extracts on this subject from various authorities. Laurillard 

 remarks that as he has found a complete similarity in the form, proportions 

 and connection of the two malar bones in several human subjects and in certain 

 apes, ie cannot consider this disposition of the parts as simply ac^dental. An- 

 other paper on this same anomaly has been published by Dr. Saviotti in the 

 "Gazzetta delle Cliniche," Turin, IStl, where he says that traces of the division 

 may be detected in about two per cent of adult skuUs ; he also remarks that it 

 more frequently occurs in prognathous skulls, not of the Aryan race, than in 

 others. See also G. Delorenzi on the same subject, "Tre nuovi casi d'anomaUa 

 dell' osso, malare," Torino, 18';2. Also, B. Morselli, "Sopra una rara anomalia 

 dell' osso malare," Modena, 1812. StiU more recently Gruber has written a 

 pamphlet on the division of this bone. I give these references because a re- 

 viewer, without any grounds or scruples, has thrown doubts on my statements. 

 ■" A whole series of cases is given by Isid. GeofEroy St.-HHaire, "Hist, dea 

 Anomalies," torn. iii. p. 437. A reviewer ("Journal of Anat. and Physiology," 



