156 SPECIMENS OF SIRENIA. 



the upper border relatively narrow. Jugal process 

 2 1 inches deep, outer surface faintlj^ concave. Palatal 

 length of preniaxilla? 2^ inches, with a rough surface ; 

 no incisor teeth, but apparently two sockets near the 

 tip ; large anterior palatine foramen. Hard palate 

 3j inches in length from most anterior molar socket 

 to tip of beak ; condyl of mandible small, convex ; 

 symphysis with rough upper surface and no teeth. 

 Mandible massive, length 9i inches, angle rectangular, 

 coronoid not pointed, broad, projecting almost hori- 

 zontally forwards. Sockets for ten molars in each 

 superior maxilla ; 1st socket empty, 2nd to 7th 

 occupied by three-fanged teeth, the crowns of which 

 are divided by a transverse groove into an anterior 

 and a posterior segment ; the 8th to 10th are not 

 erupted, the 9th and 10th being deep in their bony 

 sockets. The molars in the mandible resemble those 

 in upper jaw. The teeth are little worn. 

 From Old Calabar River. Donor — Rev. Archibald Hewan. 



2. Skull. Length in straight line 14i inches, over vertex 

 18 inches. Occipital bone ossitied, basi- fused with 

 sphenoid ; temporals detachable. Orbital aperture 

 2 inches by If inch in diameters, bony ring im- 

 perfect; anterior nares 5 inches by 3| in diameter, 

 margins sharp, somewhat rough ; septal cartilage not 

 present ; premaxillary beak not hollowed for tusks, 

 only slightly bent downwards ; no incisors, a pair of 

 circular socket-like depressions ^ inch in diameter 

 near free end ; dorsal surface of frontal grooved 

 anteriorly, flattened and expanded posteriorly, width 

 1^ inch; squamoso-zygmotic, length 4| inches by 2^ 

 high ; outer surface smooth, convex ; upper border 

 relatively broad anteriorly ; jugal process 2| inches 

 deep, outer surface faintly concave. Palatal part of 

 premaxilla 2^ inches long, surface rough; length of 

 hard palate in front of socket of 1st molar 4| inches. 

 Mandible 91 inches long, massive ; condyl small, 

 slightly convex ; coronoid broad, not pointed, directed 

 obliquely forward ; angle rectangular, inverted ; sym- 

 physis 2^ inches ; no teeth, bone rough. Upper molars, 

 ten pairs of sockets, anterior empty and partially 

 absorbed, 2nd to 7th occupied by teeth with crowns 

 only slightly worn, 9th and 10th pairs not j^et erupted 

 and concealed in their bony sockets. Lower molars 

 corresponded with upper ; the bony sac which contained 



