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and the overlying m. palato-ethmoidalis superficialis. Beyond the 

 anterior end of the palatine, the nerve lies at first between the 

 superficialis and profundus divisions of the m. palato-ethmoidalis, and then 

 penetrates and traverses the superficialis muscle, issuing on its antero- 

 lateral surface where the muscle curves mesially to have its insertion 

 on the nasal bar. No branch is given off to the muscle as the nerve 

 traverses it. Having issued from this muscle the nerve continues 

 directly forward, its relations to the muscles of the region varying 

 slightly in my several specimens. This depends on the point where 

 the nerve issues from the m. palato-ethmoidalis superficialis; the nerve, 

 when it has once passed wholly beyond that muscle, always lying at 

 first between the adjoining surfaces of the m. nasalis, m. copulo- 

 ethmoidalis, and m. copulo-tentaculo-coronarius, then on the dorsal 

 surface of the m. tentaculo-ethmoidalis, and then internal to the 

 m. ethmoideo-nasalis. There it breaks up into numerous branches 

 most of which go to the second tentacle of Ayers and Jackson's 

 descriptions, but certain of them to the dermal and other tissues of 

 the region. An important terminal branch of the nerve always passes 

 dorsal to the transverse labial cartilage and then turns downward 

 anterior to it, there penetrating two transverse subnasal muscles. These 

 two muscles are apparently both included in the Compressor oris of 

 Muller's descriptions of Bdellostoma heterotrema, and in the Trans- 

 versa oris of Fürbringer's descriptions of Myxine ; and both Müller 

 and Fürbringer say that those muscles are innervated by the ramus 

 ophthalmicus. I am, however, as in the case of the muscles said to 

 be innervated by the dorsal ophthalmic nerve, fully convinced that 

 the branch simply perforates the two muscles and does not innervate 

 either of them. That a large part of the nerve simply perforates the 

 muscles is absolutely certain. 



These two branches of the ophthalmicus trigemini, the dorsal and 

 ventral divisions of the nerve, are said by v. Kupffer to go to the 

 two anterior tentacles, one branch to each tentacle. Such is certainly 

 not the case, the dorsal nerve not sending any branches to either 

 tentacle, and the ventral branch probably not sending any branch, 

 and certainly not sending any important branch, to tentacle I of 

 Ayers and Jackson's nomenclature, which tentacle must be one of 

 the two anterior tentacles referred to by v. Kupffer. 



v. Kupffer gives two other branches of the ophthalmicus, 

 which he calls branches b and c. Branch b is said to bear two little 

 epibranchial ganglia, and to run forward under the optic nerve toward 

 the anterior end of the „Gaumenplatte". Branch c, which is said to 



