CANAL 



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CANAL 



sive. See C, Incisor. C, Incisor, a canal that 

 opens into the mouth by an aperture just behind the 

 incisor teeth of the upper jaw ; it is formed by a groove 

 on the adjoining surfaces of the superior maxillae, and 

 has two branches that open into the nasal fossae. C, 

 Incurrent, in sponges, the canals that convey water 

 from the exterior to the ciliated chambers. C, Infra- 

 orbital, a small canal running obliquely through the 

 bony floor of the orbit ; it transmits the infraorbital 

 arterv and nerve. C, Inguinal, a canal about one 

 and one-half inches long, running obliquely downward 

 and inward from the internal to the external abdominal 

 ring, and constituting the channel through which an 

 inguinal hernia descends; it transmits the spermatic 

 cord in the male, and the round ligament of the uterus in 

 the female. C, Inter-. See C, Incurrent. C, Inter- 

 cellular, in biology, canals formed by the interspaces 

 between vegetable cells. C, Intestinal, that portion 

 of the alimentary canal that is included between the 

 pylorus and the anus. C, Intrafascicular, one formed 

 in a tibro-vascular bundle by the destruction of the 

 vascular tissue and parenchyma. C, Intralobular, 

 Biliary, the radicles of the bile-ducts, forming a fine 

 network in and around the hepatic cells, and com- 

 municating with vacuoles in the cells. C. of Jacob- 

 son. See C, Tympanic. C, Kidney, in the Platel- 

 minthes, excretory tubes that take up excrementitious 

 matter from the tissues. C, Kidney, Primitive, 

 in some of the lower animals canals that appear to re- 

 place the kidneys. C. of Kowalevsky. See C, Neu- 

 renteric. C. , Lacrymal. I. The bony canal that 

 lodges the nasal duct. 2. One of the lachrymal canal - 

 iculi. d Lateral, in most fishes, two canals, one on 

 each side, that communicate with cavities in the head, 

 and with the exterior, by apertures in each overlying 

 scale ; they are probably sensory in function. C. of 

 Laurer, in certain worms, one by which the oviduct 

 opens externally on the dorsal surface ; according to 

 some, the vitellarian duct. C, Lingual, in the horse, 

 etc. , the floor of the mouth, from its lodging the tongue. 

 C. of Loewenberg, that portion of the cochlear canal 

 that is situated above the membrane of Corti. C, 

 Longitudinal, in the Cestoda, canals, one on each 

 side of a joint ; they are of uncertain function. C, 

 Looped, in the Annulata, the segmental organs. C, 

 Macro-myelonal, the central canal of the spinal cord. 

 C, Madreporic, in the Echinodermata , one joining 

 the madreporite, and the circular canal. C, Malar, one 

 in the malar bone transmitting the malar division of the 

 temporo-malar branch of the superior maxillary nerve. 

 C. of Marrow. See C. , Cartilage. C, Maxillary. 

 See C, Dental. C, Median. I. The central canal 

 of the spinal cord. 2. The aqueduct of Sylvius. C, 

 Medullary, i . The hollow cavity of a long bone, con- 

 taining the marrow. 2. See C, Vertebral. 3. The cen- 

 tral canal of the spinal cord. 4. An Haversian canal. 5. 

 The canal of De Candolle, enclosing the pith in the 

 stem of plants. 6. In embryology, the medullary tube. 

 C, Medullary, Cerebro-spinal, the central canal of 

 the spinal cord. C, Membranous, of the Cochlea, 

 a canal in the cochlea, following the turns of the 

 lamina spiralis ; it is bounded by the basilar mem- 

 brane, the membrane of Reissner, and the wall of 

 the cochlea. C, Membranous, Semicircular. 

 See C, Semicircular. C. of Modiolus, the spiral 

 canal of the cochlea. C, Muciparous. See C, 

 Mucous. C, Mucous, in general, canals lined 

 with mucous membrane. In zoology, canals found 

 beneath the scales of fishes and other scaly animals, 

 furnishing the mucus that lubricates the surface. C. 

 of Muller. See Miillerian Duct. C, Myelonal, the 

 central canal of the spinal cord. C, Nasal. I. See 



C, Lachrymal. 2. An occasional canal found in the 

 posterior portion of the nasal bone ; it transmits the 

 nasal nerves. C, Naso-lachrymal. See.C, Lach- 

 rymal. C, Naso-palatine. See C, Incisor. C, 

 Neural. 1. See C, Vertebral. 2. In Echinoderms, 

 a canal a part of the wall of which is formed 

 by the ambulacral nerve and its connections. C, 

 Neurenteric, of Kowalewsky, also called Blasto- 

 poric Canal, in the embryo, a passage leading from 

 the posterior part of the medullary tube into the arch- 

 enteron. C, Neuro-central. See C, Vertebral. C. 

 of Nuck, a pouch of peritoneum which, in the female 

 fetus, descends for a short distance along the round 

 ligament of the uterus into the inguinal canal ; it is the 

 analogue of the processus vaginalis in the male. It 

 sometimes persists after birth. C, Nutritive. See C, 

 Haversian. C, Obstetric. See C, Parturient. C, 

 Obturator, a canal in the ilium transmitting the obtu- 

 rator nerve and vessels. C, Olfactory, in the embryo, 

 the nasal fossae at an early period of development. C, 

 Omphalo-mesenteric, in the embryo, a canal that 

 connects the cavity of the intestine with the umbilical 

 vesicle. C, Optic. See Optic Foramen. C, Orb- 

 ital, Anterior Internal. See C, Ethmoidal, An- 

 terior. C, Orbital, Posterior Internal, the poste- 

 rior of two canals formed by the ethmoid bone and 

 the orbital plate of the frontal. It transmits the pos- 

 terior ethmoidal vessels. C, Palatine, Accessory 

 Posterior, one or two canals in the horizontal plate 

 of the palate bone, near the groove entering into the 

 formation of the posterior palatine canal. C., Pala- 

 tine, Anterior, formed by the union of the incisive 

 canals; it opens on the palate behind the incisor 

 teeth. C, Palatine, Descending. See C. , Palato- 

 Maxillary. C, Palatine, External, Small, a small 

 canal in the pyramidal process of the palate bone, 

 close to its connection with the horizontal plate. It 

 transmits the external palatine nerve. C, Palatine, 

 Posterior. See C. , Palato-maxillary. C, Palatine, 

 Smaller. See C, Palatine, Posterior. C, Palatine, 

 Superior, one formed by the palate bone and the 

 superior maxilla, transmitting the large palatine nerve 

 and blood-vessels. C, Palato-maxillary, one formed 

 by the outer surface of the palate bone and the adjoin- 

 ing surface of the superior maxilla. It transmits 

 the large palatine nerve and blood-vessel. C, Para- 

 gastric, in the Ctenophora, one that branches off on 

 each side of the funnel, and terminates near the oral 

 extremity of the funnel. C, Parturient, the channel 

 through which the fetus passes in parturition, includ- 

 ing the pelvic canal, and the uterus and vagina con- 

 sidered as a single canal. C, Pelvic, the canal of 

 the pelvis, from the superior to the inferior strait. C, 

 Pericardio-peritoneal, in some of the lower verte- 

 brates ; canals connecting the pericardium and the 

 peritoneal cavity. C, Perigastric, in the Hydrozoa, 

 two canals running parallel to the stomach, from the 

 infundibulum, and terminating in culs-de-sac near the 

 mouth. C, Peritoneal, in the Plagiostomata, etc., 

 two canals leading from the peritoneal cavity, one to 

 each side of the cloaca. C, Perivascular, the cir- 

 cumvascular lymph spaces. C. of Petit. Properly, 

 a space, intersected by numerous fine interlacing fibers, 

 existing between the anterior and posterior laminae of 

 the suspensory ligament of the crystalline lens. It 

 extends from the periphery of the lens, nearly to the 

 apices of the ciliary process, and transmits the secre- 

 tion from the posterior chamber. C, Petro-mas- 

 toid, a small canal not always present, situated at the 

 angle of union between the mastoid and petrous bones. 

 It transmits a small vein from the middle fossa of the 

 skull to the transverse sinus. C, Petrosal, two canals 



