THE ORIGIN OF MAN 113 



into the streets that every developing individual recapitulates 

 the story of his race that he climbs his own ancestral tree. 

 It is obviously out of regard to this dictum that our text-books 

 sometimes lull the student's propensity to inquire by vague 

 statements that traces of the facial suture lines are commonly 

 present in the human skull at birth. It must also have been 

 in some such way that the distinguished author of the Cart- 

 wright Lectures of 1892 told his audience that the human 

 premaxilla is sometimes partially and sometimes, but more 

 rarely, wholly isolated, and that it is late to unite with the 

 maxillary in Australians, and in some examples of New 

 Caledonians and Greenlanders. It is strange that we have 

 not yet been told the actual facial articulations of this separ- 

 ate human premaxilla ; for these articulations differ widely in 

 the different groups of monkeys, and it would be extremely 

 interesting to know them in Homo. 



Now the actual facts of the case are very different ; for 

 it is only at its very first appearance as a cartilaginous 

 nucleus that the premaxilla is separated from the nucleus of 

 the facial part of the cartilaginous human maxilla. When 

 the human embryo is no more than 19 mm. long that is, 

 about ten times the diameter of an ordinary pin's head 

 the premaxilla is losing its identity in the cartilage of the 

 maxilla, and when the embryo is another 5 millimetres longer 

 it has ceased to exist as a separate entity on the face. The 

 process by which the facial portion of the premaxilla becomes 

 lost as a separate element is a complicated one, and it involves 

 far more than the mere loss of a superficial suture line, for the 

 whole method of growth of this part of the face is involved. 

 The human premaxilla is lost in, and becomes overgrown 

 by, the facial portion of the maxilla, but it still shows its 

 independence of the maxilla, not only upon the palate but 

 within the nasal chambers. How very different a story is 

 this from what Haeckel would have had us believe. We 

 have been told by him that the developing human embryo 

 could not be distinguished from the embryo of an anthro- 

 poid ape until the fourth or fifth month of pregnancy. Yet 

 here is a detail which is absolutely diagnostic of Homo as a 



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