406 



Harris Hawthorne Wilder 



between the roof of each orbit and the eyeball, and issues forth to supply 

 its half of the forehead as though both the latter and the nerve pair were 

 those of a single normal individual. A special interest must attach to 

 median parts, especially when thin, like the nasal septum ; but this, as well 

 as the crista galli and the two olfactory fossse lateral to it, appear precisely 

 as in the head of a normal fetus of the same age. In the same way the 

 suture between the two frontals is in no respect different from that which 



Fig. 25. Dissection of tlie double eyeball of the Baldwin Synote. The 

 three views represent progressive stages in the dissection. 



fr, frontal ; oph, ophthalmic branch of the Trigeminus ; trc, rudimentary 

 tarsal cartilage; pc, "palpebral canal"; ms, median suture between the two 

 frontals; 1, 2, and 3, muscles explained in the text; Ip, levator palepebrae; 

 nx, an unlcnown nerve ; bx, an unlinown bulbous organ. 



in normal cases separates the two frontal bones which belong to the two 

 halves of a single body. 



Upon the imperfect side the double median eyeball lies immediately 

 beneath a bony bridge that is evidently composed of the orbital plate of 

 the double frontal, here united into a single bone without a trace of 

 double origin. The eyeball is covered by a series of narrow band-like 

 muscles, arranged in perfect bilateral symmetry, those of the two sides 

 separated by a median artery. As seen from above, these muscles are four 

 in number upon each side. Of these the innermost pair is innerved by the 



