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consideration has been already separated into three parts, one of 

 which here turns downward and goes to tentacle 4 ; this nerve in 

 each of three specimens that I examined separating into two parts 

 one of which perforated the m. copulo-tentaculo-coronarius near its 

 ventral end. The other two parts of the main nerve continue for- 

 ward immediately internal to the m. tentacularis posterior, passing 

 ventral to a ligamentous band that connects the lateral labial car- 

 tilage with the cornual cartilage, and that is shown by Müller in 

 one of his figures (18, Fig. 6, PL 3). The two branches are then 

 distributed the one to tentacle 3 , and the other to tentacle 1 . 



All three branches of this anterior branch of the ramus maxillo- 

 mandibularis lie always immediately internal to the m. copulo-palatinus 

 profundus, and, anterior to that muscle, immediately internal to the 

 m. tentacularis posterior. They all pass lateral, and hence dorsal to 

 the lateral labial cartilage to reach their respective tentacles, thus 

 having to that cartilage the relations that the ramus maxillaris tri- 

 gemini in other fishes has to the palatine cartilage. The two branches 

 that go to the first and third tentacles both pass ventral to the 

 ligament that extends from the cornual cartilage to the lateral labial 

 cartilage, the latter cartilage here lying mesial to the former. Be- 

 cause of this relative position of these two cartilages it is evident 

 that the two nerves lie external to the ligament. Therefore, if the 

 lateral labial cartilage be the homologue of the piscine palatine, as 

 its relations to the nerves indicates, these nerves must lie morpho- 

 logically dorsal to the ligament, though actually ventral to it. As to 

 the branch that goes to tentacle 4 , it runs downward in that tentacle. 

 If then the tentacle forms part of the upper lip, as Parker asserts, 

 the nerve must run morphologically backward in it, thus having to 

 this tentacle much the general relations that the maxillary branch of 

 my descriptions of the maxillaris superior trigemini of Amia has to 

 the maxillary of that fish. The cartilage of the tentacle, in Bdello- 

 stoma, may therefore represent the cartilage that, according to Sage- 

 mehl (27), underlies primarily the maxillary bone of Teleosts and 

 Ganoids. No branches go from either of the three nerves to any of 

 the muscles of the region, but the nerve that innervates the m. qua- 

 drato-palatinus often has its apparent origin from the ramus ad tent. 4 , 

 as will be later shown. The entire nerve thus must be the maxillary 

 nerve of v. Kupffer's descriptions, but that author says that that 

 nerve is only distributed to the two posterior tentacles, which is cer- 

 tainly an error. Taken together with an important branch, described 

 below, of the motor nerve of the complex, it forms nerve 6 of 



Anat. Anz. XXIII. Aufsätze. 18 



