16 H. B. POLLARD. 



Sensory Tentacular Nerves of Callichthys (Fig. 10). 

 The main stem of the Trigeminus passes below the eye giving off 

 behind that organ a palatine branch, which divides into several small 

 twigs supplying the roof of the mouth. 



Below the centre of the eye the main stem divides into two 

 branches, an upper and lower. The upper gives off shortly a Ramus 

 premaxillaris (R. p»ix.) and, as the Ramus maxillaris (R. mx.), runs 

 forward along with the R. premaxillaris in a space between the adductor 

 mandibulae and adductor arcus palatini muscles. The Ramus pre- 

 maxillaris gives off small branches to the skin in the antorbital region 

 and passes forward, lying near the skin outside the prepalatine piece, 

 dividing into small twigs in the premaxillary region. 



The Ramus maxillaris, running forward, divides into (1) a small 

 branch which passes outwards and downwards and along the posterior 

 face of the coronoid tentacle, (2) a large branch which runs down 

 outside the maxillary tentacle and divides into four twigs, two of 

 which supply the anterior and lateral face of the coronoid tentacle, 

 and the other two the posterior face of the maxillary tentacle, (3) a 

 branch which divides above the velar support, some twigs supplying 

 the lateral part of the anterior region of the roof of the mouth, the 

 remaining branch passing down inside the maxillary tentacle to supply 

 its anterior face. 



The Ramus mandibularis (R. md.) gives off a Ramus coronoideus 

 (R. cor.), which is small and runs above and outside the adductor 

 mandibulae muscle, turning down to supply the posterior face of the 

 coronoid tentacle. 



Continuing forwards and downwards, through the adductor mandi- 

 bulae muscle, the Ramus mandibularis divides into R. R. mandibulares 

 externus ( R. md. ext.) and internus.' The R. mandibularis externus 

 lies outside the muscle and gives off a small branch, which runs down- 

 wards and backwards to the skin outside the Meckelian cartilage, 

 thence, passing outside the anterior portion of the Meckelian cartilage, 

 it continues forwards internal to the maxillary and coronoid tentacles, 

 and reaching the mental tentacle, it divides into three small twigs, 

 which supply the anterior face of this tentacle, the skin there being 

 remarkably rich in sense organs. 



The Ramus mandibularis internus divides above the Meckelian 

 cartilage into R. submandibularis (A', subm.) and R. mentalis (R. ment). 



