OCR Text |
Show PROC. ZOO] TELEOSTEI. I. E L A EI. b. T E L E 0 S T K O I D E I. &|-.NE:iAL FUNERAL FEATURES OF THE CANALS AND BRANCHES. Th- canals u)s protected by scales, and pass through open grooviies of the head. They are Hcptabranvl lachiis, Hctc Branching fine dendrit the Lateral canals and ventral surf: Cluster and Accessory sen canal-systen Occipital comiital commissure present, also in frontals oidosteus) and in ethmoid (Polypterus). gfltic branching profuse in Lepidosteus. branches from the Lateral canal. prfer and primitive pores usually few. oessory sensory organs. INNERVATION. . Lateral Cafyral Canal. X. Vagi lateralis. 2. Main CanaL® Canal. X. Branch from vagi ganglion ^eralis, IX. Glossopharyngeal, and V. 4U1U8 oticus. 3. Occipital CHpital Commissure. Branch from X. ganglion, agi lateralis. 4. Hyo-mandderculo-mandibular branch. VII. Kamns hyo-mandjyo-mandibularis. 5. Supra-orbitpra-orbital branch. VII. Ramus oph-thalmicus| ialmicus superficialis. 6. Sub-orbitaslo rbitol branch. VII. Ramus buccalis. 6. Tbe Glossoph does not ent canal-system f To face p. 888. IV. T E L E O S T E I. GENERAL FEATURES OP THE CANALS AND BRANCHES. Canals sometimes dermal (Amiurus) or protected by scales or drain-pipe-like canal-bones, or represented only by sensory organs, or both absent (Ostradons, Gentriscus). In some cases (Coris) the canal passes through modified scales only. In Exocetus the Lateral canal passes dorsal to tbe pelvic fin and ventral to the pectoral, the canals of either side converging ventrally. In Conger, Solea, &c, saccular dilatations pass off from tbe canals. In tbe deep-sea Teleosts, e. g. Cottus bathybius, Liparis micropus, Lycodes murcena, &c, the canals are in the form of open grooves. In some Pleuronectidse 2 or 3 lateral canals. Iu Mugil 9 are present (M'Donnell). Occipital commissure nea-ly always present, sometimes one in frontal region. Dendritic branching occasionally present. Cluster and primitive pores few, where present. Accessory sensory organs sometimes occur (Amiurus, &c). INNERVATION. 1. Lateral Canal. X. Vagi lateralis. In the Ostracions the vagi lateralis is more or less rudimentary (Giinther). 2. Main Canal. V. Ramus ophthalmicus superficialis, the ramus oticus sometimes (Amiurus); the glossopharyngeal may either innervate a portion or the whole. The vagus may or may not by anterior branches supply the initial portion of the main canal. 3. Occipital Commissure. Glossopharyngeal. 4. Operculo-mandibular branch. VII. Ramus byo-mandibularis. In Amiurus, ramus oticus and ramus mandibularis (V.). 5. Supra-orbited branch. V. Ramus ophthalmicus superficialis. Sub-orbital branch. V. and ramus maxillaris. Ramus buccalis |