Landacre, Taste Buds of Jmenirus. 



29 



there is an area devoid of buds between the two groups. This 

 is the only case in which two groups which later become con- 

 tinuous are at all difficult to separate at the time of their first 

 appearance. 



7. THE POST-ORBITAL AND OPERCULAR GROUP. 



A fourth group comprises buds lying back of the eye mainly, 

 and in front of the posterior edge of the operculum. The 

 various divisions of this group arise almost simultaneously, but 

 receive their nerves from a variety of sources. Two other groups, 

 the cerebellar and the occipital groups, belong here as far as 

 their position on the longitudinal axis of the body is concerned; 

 but since they appear much later and have in addition their 

 nerves in common with the body buds, they will be described 

 with those of the body. 



The post-orbital group can be divided into several smaller 

 subdivisions as follows: 



(A) Buds lying behind, under and above the eye and inner- 

 vated by fibers from the ramus max. acces. and the ramus mand. 

 ex. VII. 



(B) Buds lying on the mandible and distributed along the 

 mandibular lateral line canal from lateral line organs three to 

 eight and innervated by the ramus mand. ex. VII. 



(C) Buds lying on the operculum, those in the region of the 

 pre-operculum bone being innervated by the ramus mand. ex. 

 VII, while those lying on the posterior and dorsal portions of 

 the operculum in the region of the post-frontal and squamosal 

 are innervated by the ramus oticus. 



(D) Buds lying on the branchiostegal rays and innervated by 

 the ramus hyoideus. 



TABLE VIII. 



Table showing the number and time of appearance of buds in the post-orbital group. 



