of Edinburgh, Session 1884-85. 
17 
an imperfect union of the two hones may arise. Should the bones 
remain separate, and should the want of union be accompanied by 
anon-closure of the superjacent soft parts, then the imperfect de- 
velopment would lead to the production of a cleft in the alveolar 
region and in the upper lip, and the theory of Goethe might there- 
fore be applicable to such cases. 
The author then referred to the descriptions of Leidy, Callender, 
and Th. Kolliker on the development of the intermaxillary bones. 
B. The object of examining the hard palate where there was no 
cleft was to ascertain if any suture, or the remains of a suture, could 
be seen in its anterior part, immediately behind the incisor teeth, to 
indicate that, as Dr Albrecht contends, the incisive or intermaxillary 
element of the human upper jaw had originally consisted of two 
bones on each side, a mesial or internal, and a lateral or external. 
The author described six specimens, in each of which a narrow fissure 
was present in each intermaxilla, which apparently represented the 
remains of an intra-incisive suture. It existed in conjunction with 
a pair of maxillo-in term axillary sutures. 
The place of origin of the intra-incisive fissure in the majority of 
the specimens was from the maxillo-premaxillary suture external to 
the incisive canal, which canal, therefore, on the theory that the 
intermaxilla consists of an inner and an outer division, would lie in 
relation to the inner division close to the articulation between it 
and the superior maxilla. In one instance the intra-incisive fissure 
penetrated into the naso-palatine canal. Obviously, therefore, some 
condition arising during the development of the bone determined 
the origin and direction of the fissure in question. 
What is yet wanted, however, in order to give completeness to 
the evidence of the division of the intermaxillary bone into an inner 
and an outer part, is the discovery that the intermaxillary bone 
normally arises from two distinct centres of ossification, one for the 
inner, the other for the outer part. Of this there is at present no 
evidence. But, in connection with this matter, it ought not to be 
forgotten that it is only recently that the embryological evidence of 
the origin of the intermaxillary part of the human upper jaw, from 
a centre distinct from that of the superior maxilla, has been com- 
pleted. And yet for nearly a century, on such minor evidence as 
was advanced by Goethe, viz., the suture on the hard palate extend- 
VOL. XIII. 
B 
