30 'Journal of Comparative Neurology and Psychology. 



Subdivision A does not appear until in the ii mm. embryo, 

 where there are six buds present, one under the eye, four on 

 the dorsal and posterior portion of the cornea and one behind 

 the eye. Of the ten buds present in series A in the I4f mm. 

 embryo, eight lie on the upper and posterior portion of the eye 

 and two behind the eye, none being present under the eye. 



This subdivision is distinctly isolated in position from other 

 members of the group to which it belongs. It is, however, not 

 so sharply separated from the posterior buds of the nasal group 

 as adjoining groups are usually separated. Even in this case, 

 however, there is an area of 20 sections between the anterior 

 buds of group A and most posterior buds of the nasal group. 

 In addition, the posterior buds of the nasal groups are above 

 the anterior half of the eye and the first buds of the orbital sub- 

 division appear under and behind the eye. 



The first buds to appear in this subdivision are situated on 

 the border of the cornea, some of them actually lying on the 

 transparent portions of that structure. 



Without raising any question as to the relation of the acces- 

 sory maxillary -nerve to the ramus maxillaris, it may be of 

 interest to note that the taste buds innervated by the ramus max. 

 lie on the lateral portions of the upper lip, on the maxillary 

 barblets, and on the skin of the upper lip, just anterior to the 

 maxillary barblet at the extreme anterior end of the embryo 

 and appear more than 130 hours sooner than those lying about 

 the eye and supplied by the ramus max. acces. 



The second subdivision B appears first in the 11 mm. em- 

 bryo, where there are at least eight buds. It is not present in 

 series U (244 hours). The whole mandible, as mentioned above 

 in the adult (Herrick, '01), is supplied with two nerves; first, 

 in common with the lower lip and mental and post-mental bar- 

 bules, by the ramus mand. V, external branch, and secondly, 

 by the ramus mand. VII, a branch of the ramus hyomandibularis. 

 This last nerve supplies the mandible from the region of the 

 third of the main lateral line organs back to the region of the 

 seventh, or possibly farther. In the earlier stages, however, 

 the groups supplied by these two nerves are quite distinct. The 

 anterior mandibular group spreads back from the lips and men- 

 tal and post-mental barbules and appears much earlier, while 

 the posterior group comes in with the remaining divisions of 



