668 E. PH. ALLIS, 



On leaving the anterior end of the anterior squamosal ossicle, 

 the main infraorbital canal enters a canal in Bridge's bone C^, a 

 bone which both Bridge and Collinge consider a single one, and 

 which they both homologize, as already stated, with the dermo- 

 sphenotic of other fishes. This bone is not, however, a single bone, 

 either in my prepared skull or in either of the several other specimens 

 examined, there being composed, in each case, of three or more wholly 

 separate and distinct bones. The two principal bones here concerned 

 are, however, so closely and intimately applied to each other that 

 they might easily be mistaken for a single piece, and this doubtless 

 misled both Bridge and Collinge ; for I can not believe that these 

 bones were not separate and independent in their specimens as well 

 as in mine. The remaining one or more bones that also enter into 

 the bone C^ are little lateral sensory ossicles that might possible have 

 been lost in dissection by Bridge and Collinge; but I think it much 

 more probable that they were seen but considered, as the other two 

 larger bones certainly were, as parts of a single bone. This very 

 mistake was, in fact, first made by both my assistant, Mr. Nomura, and 

 myself, when examining cursorily the bones of the prepared skull ; for 

 although this skull had been kept some ten years in alcohol, and had been 

 shaken about considerably in transportation, three wholly separate and 

 independent bones were closely united to form what was apparently a 

 single bone, and which corresponded exactly with bone C'^ of Bridge's 

 descriptions. 



The two or more additional bones thus here represented in the 

 single bone C^, complete the otherwise incomplete number of the 

 dermal elements of this part of the skull, and permit an inter- 

 pretation of the several cranial bones not otherwise arrived at. As, 

 however, two different interpretations can be given to the several 

 bones here concerned, between which I hesitate to decide, I shall 

 call them for the present, bones i, 2 and 3; bone 3 being re- 

 presented by the one or more little lateral sensory ossicles above 

 referred to, together with certain more anterior ones that seem 

 to have entirely escaped the notice of both Bridge and Collinge. 

 These several bones are all shown in the figures, and no special de- 

 scription of them is necessary. A large lateral portion of bone 1 lies 

 directly upon the mesial portion of the posterior half of bone ^, while 

 its mesial edge articulates by sutures with bones B^ and JS^ of 

 Bridge's descriptions, the articulation being more important with B'^ 



