Coues.] 96 [June 16, 



at the base of the great fissure. Notwithstanding their small size, 

 the orbital cavity has a number of muscles of little less than ordinary- 

 dimensions, but scarcely recognizable in consequence of imperfect or 

 faulty insertions, and displaced origins from the distortion of the 

 bony parts. The optic nerves emerge from the cranium at the bottom 

 of a large opening. 



The superior maxillary divisions of the fifth pass through this same 

 opening, across the floor of the orbital fossa, into and through the 

 maxillary foramina (which are placed side by side, near the median 

 line of the skull) and ramify in an undistinguishable mass of muscu- 

 lar and cellular tissue that lies upon the bones and forms the cheek 

 and upper lip. 



As is usual in these cases, the great commissure of the brain is 

 "wanting, the cerebral hemispheres being fused and presenting a single 

 smooth convexity. 



Such are the principal features of the soft parts chiefly concerned 

 in the formation of the monstrosity ; the shape and position of many 

 of the cranial bones is equally anomalous. The osseous abnormities 

 increase in number and degree from behind forward,. as would nat- 

 urally be expected, and culminate among the elements of the " rhin- 

 encephalic vertebra." Remarkable openings in the skull occur, 

 isolating the several arches in great measure, and exhibiting them to 

 the physical eye as clearly as they can be seen with the mind's. 

 Particularly in the case of the fourth or anterior segment of the 

 skull, we have the unusual spectacle of the centrum and haemal arch 

 distinct and removed from the neural; the latter alone enclosing the 

 neural axis; and the former hanging from the cranium, somewhat 

 after the manner of the succeeding haemal arch (lower jaw), sus- 

 pended by its own pleurapophysis alone, and not otherwise attached 

 to the rest of the skull than by the zygoma. The general condition, 

 in fact, comes near being an ocular demonstration of four vertebrae 

 in the mammalian skull. 



Detailed descriptions of the bones principally concerned will follow; 

 we have here to note first the general condition of the skull as a 

 whole, and next as composed of several segments. 



The base of the cranium proper presents three principal openings 

 or foramina lacera, succeeding each other from behind forward. The 

 first of these appears to correspond to, and to result from, the con- 

 fluence of the fissurae lacerae posteriores and mediae. It is an irreg- 

 ularly crescentic opening (one on either side the basi-occipital and 



