. A course of instruction in zootomy (vertebrata). Anatomy, Comparative. THE SKATE. Si The vestibule is a rounded sac with two small diverticula, containing an otolithic mass which consists of minute calcareous particles bound together by gelatinous connective tissue : from its dorsal surface pro- ceeds a canal, the aqueductus vestibuli (), which passes through the roof of the auditory capsule, and dilates between the latter and the external integument into a small sac, lined with strongly pigmented epithelium ; this opens on the surface of the head by a minute aperture. The canals form ne
. A course of instruction in zootomy (vertebrata). Anatomy, Comparative. THE SKATE. Si The vestibule is a rounded sac with two small diverticula, containing an otolithic mass which consists of minute calcareous particles bound together by gelatinous connective tissue : from its dorsal surface pro- ceeds a canal, the aqueductus vestibuli (), which passes through the roof of the auditory capsule, and dilates between the latter and the external integument into a small sac, lined with strongly pigmented epithelium ; this opens on the surface of the head by a minute aperture. The canals form nearly complete circles, the posterior being the largest of the three. Each is dilated at one part of its course into an ampulla (a). The posterior canal communicates with the vestibule in an unusual manner, namely by a short distinct tube (x). ^ } FiG. 28.—Raja batis. The right membranous labyrinth, seen from the outer side (nat. size). v, vestibule: , aqueductus vestibuli : , anterior, , posterior, and , horizontal semicircular canals : a,a,a, ampullae : X, side tubulure by which the posterior canal communicates with the vestibule : n,n,n, branches of auditory nerve. XLVII. Clear away the skin and muscles from the •/ dorsal surface of the anterior vertebral plate and from that of the gills. Dissect out 214. The vagus or tenth nerve (Fig. 22, X], which, after leaving the skull by the vagus foramen, passes directly back- wards between the inner boundaries of the gills and the lateral ridge of the anterior vertebral plate, giving off the branchial nerves as it goes, to the front edge of the pro- pterygium, where it divides into two chief branches, a ventral branch (X,v), to the stomach and heart, and a lateral branch ,f), which passes between the peritoneum and dorsal G. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectanatomy, bookyear1884
