108 



ZOOLOGY 



SECT. 



line system, having at first a metameric arrangement, also occur 

 in the aquatic Amphibia. 



The function of the neuromast-organs has been shown to be 

 to enable the animal to detect vibrations in the water of too low 

 a frequency to form a sound capable of perception by the ear. 



R 



f 



FIG. 781. A, Sensory canals of the left side of the head of a Bony Fish. (From the Cambridge 

 Natural History, after Cole.). B, organ of the lateral line (neuromast)in a tailed Amphibian 

 (semi-diagrammatic) a, epidermic cells, through which are seen 6, sensory cells ; c, sensory 

 hairs ; N, nerve ; R, hyaline tube. (From Wiedersheim's Vertebrata.) 



The sense of taste has for its special organs taste-buds (Fig. 

 782), similar in general character to the end-buds in the skin, and 

 composed of groups of narrow rod-shaped cells. In Fishes these 

 are widely distributed in the mouth and branchial cavities, 

 also on the outer surface of the head, and in some Fishes 



