204 ME. F. J. COLE ON THE STEUCTUEE AND MOEPHOLOGY OF 



skeleton of the head, and on their disappearance left a legacy to the skull in the shape 

 of certain of the lateral line ossicles, which either on account of additions to their 

 original function were retained as new elements, or were fused on to, and came to form 

 a part of, hones previously existing. 



6. The ganglia of the trigeminal and facial nerves have fused to form an elaborate 

 complex, in which the individuality of the ganglia has been lost, and which arises from 

 the brain by two roots. The ganglion in connection with the lateral line nerve is, 

 however, distinct. The sympathetic trunk is connected with the vagu.s, glossopharyngeal, 

 and trigemino-facial ganglia. 



7. A portion of the trigemino-facial complex which is connected with visceral 

 sensory fibres, and which I have called the facial ganglion, is in such a condition as to 

 strongly suggest the view that it is migrating from the complex and is in process of 

 being converted into a sympathetic ganglion. It is in connection with the sympathetic 

 trunk, and has been described by many authors as a symjiathetic ganglion. The 

 condition of this ganglion favours the view that at least the greater part of the facial, 

 glossopharyngeal, and vagus nerves of Fishes belongs to the sympathetic system. 



8. A typical branchial nerve has the constitution tabulated on p. 144. 



9. The facial nerve of Man and Mammals can be derived from the branchial facial 

 nerve of a fish. 



10. The anastomosis of Jacobsou is the visceral sensory palatine or visceral branch of 

 the IXth, and connects the glossopharyngeal ganglion with the ramus palatiuus facialis 

 (also visceral sensory). It is neither a somatic sensory nor a lateral line anastomosis, and 

 cannot be homologiscd with either of these. 



11. The lateral line system of Fishes is, as far as our present knowledge goes, not 

 metameric. This conclusion is supported by the whole of the anatomical and part of the 

 embryological evidence. The observations under the latter head that have hitherto been 

 considered to support the metameric view of the lateral organs are certainly in part, if 

 not entirely, concerned with another series of sense organs, and do not relate to the 

 lateral sense organs at all. 



12. The nerves supplying the lateral sense organs (both superficial and canal) form a 

 separate series in themselves, and are not connected with any of the other cranial nerves , 

 They may be named the Superficial Ophthalmic, Buccal, External Mandibular, and 

 Lateralis Lateral line Nerves. The innervation of the lateral sense organs of Fishes and 

 Amphibia is remarkably constant, and should be taken as the guide in determining the 

 limits of a canal. The sensory canals and pit organs of Gadiis are innervated by the 

 branches of these nerves — the glossopharyngeus taking no part in the innervation of the 

 system either in Gaclus or morphologically in any other form. 



13. The system of nerves known as the ramus lateralis trigemini is a ganglionated 

 system of somatic sensory nerves formed typically of the dorsal branches of the Vth, 

 Vllth, IXth, and Xth cranial nerves, with a certain number of the same branches of the 

 spinal nerves, all more or less fused together, and forming the sensory nerve supply of all 

 the fins of the body. Its common name, therefore, should be abandoned in favour of its 

 oriu'inal name of ramus lateralis accessorius. 



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