TWO FIGCRES
General chemical sense is considered as distinct from the sense of taste (Best and Taylor, '43, p. 1785). The latter is associated with taste buds and the afferent visceral components of cranial nerves VII, IX, and X. Chemical sensibility is mediated by free cutaneous nerve endings and spinal nerves.
It has been pointed out (Kappers, Huber, and Crosby, '36, 1 : 347) that, in addition to having separate neural mechanisms, the 2 types of perception are also different in their biological significance. The sense of taste is instrumental in bringing about positive reactions to food substances. By contrast, reactions due to the stimulation of the chemical sense are said to be negative, i.e., they are defense reactions. This differentiation is based in part on the behavior of the sea robin, Prionotus, as observed by Herrick ( '04).
More recent observations of positive reactions to food which were obtained by stimulation of skin lacking taste buds in the closely related Mediterranean sea robin, Trigla ( Scharrer, '35), seem to be at variance with this concept. Since Herrick did not observe positive reactions to food in Prionotus, ex- periments similar to those made previously on Trigla were repeated in the present studies on Prionotus in order to This study was aided by a grant of the Rockefeller Foundation.