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in the midline, This has a little recess just in front of it. This 
process (Fig. 9) seems to represent the undeveloped mandibular divisions 
of the first branchial arch and the cleft in front represents the un- 
developed stomodeum and the unruptured buccopharyngeal membrane. 
Just caudad to the above process is the transverse slit that extends 
from pinna to pinna and leads into pharynx and larynx. Upon 
dissecting the submaxillary region considerable muscle is seen beneath 
the skin but no oral cavity demonstrable, as the muscle covers the 
palate. Upon cutting through the palate the re normal nasal 
fossae were exposed. 
Just within the ventral wall of the slit is seen a rather broad 
but short process, the rudimentary tongue.- On the dorsal wall the 
two arches of the soft palate are prominent, but the nasal cavities are 
separated from the pharynx by delicate membranes (easily loosened) 
that covers in each arched space. 
The maxilla on each side failed to develop in a normal manner, 
the palate is narrow, there are neither alveolar processes nor teeth 
and the bony orbital floor is wanting. Apparently here there was a 
failure of development of mandibular arches, especially followed by a 
failure of rupture of the buccopharyngeal membrane and the consequent 
lack of an oral cavity. To offset this nature apparently opened the 
first cleft to thus establish a connection with the pharynx and larynx. 
11. This specimen (Fig. 10) is of a head of a calf at term. It 
presents one pair of eyes, one pair of ears, but four nares in the 
broad nasal area. No external indication of four maxillae is noticeable. 
The lower jaw shows a slight indentation between the partially divided 
mandible. Upon examination of the oral. cavity, a double cavity is 
manifest. ‘The tongue, though apparently double, is found to have a 
single root. ‘There seems to be two mandibles, each having the incisor — 
teeth in excess, there being eight in each instead of six. An inter- 
mandibular ridge separates the two mandibles in the molar teeth — 
portions. The ridge continues dorsally between the two apical portions 
of the tongue to the single base; there the ridge arches up over the 
base to be attached to the roof of the oral cavity. The palate consists 
of a narrow median portion separated on each side from the palatal 
#) 
shelves by a wide cleft through which the large soft nasal septum 
can be seen. The palatal rugae are well developed. 
Another malformation exists at the vertex of the skull; apparently 
the vertical portion of frontal, the tabular portion of the occipital, the 

