author's abstract of this paper issued 

 ht the bibliographic service, may 24 



THE NERVE AS A FORMATIVE INFLUENCE IN THE 

 DEVELOPMENT OF TASTE-BUDS 1 



J. M. D. OLMSTED 



Department of Physiology and Physiological Chemistry, College of Medicine, 

 University of Illinois, Chicago, Illinois 



INTRODUCTION 



The influence of one organ upon the development of another 

 is a fundamental problem in morphogenesis. Embryologists 

 have rather taken for granted that the differentiation of special- 

 ized organs, such as the transformation of epithelial cells into 

 taste-buds, is due to the growth of the appropriate nerve into the 

 region concerned. Hermann ('84), who first described the de- 

 velopment of taste-buds in the dog, seems toholdthis view, though 

 he states that one sees the embryonic nerve beneath the germi- 

 native layer of the epidermis after the dermal papilla appears. 

 The nerve then passes up to the forming taste-bud, and finally the 

 characteristic spindle-shaped taste-cells become differentiated. 



Marchand ('02), who studied the developing papillae in the 

 human foetus, states: "Vers le cinquieme mois, certaines cellules 

 de la couche generatrice commencent alors a se differencier pour 

 donner naissance aux borgeous gustatifs. Les nerfs gustatifs qui 

 commandent la differentiation sont arrives au contact de Peri- 

 thelium." 



Landacre ('07), in his paper on the place of origin and distribu- 

 tion of taste-buds in Amiurus melas, says, in regard to the ques- 

 tion whether the taste-buds appear fortuitously and are later 

 connected with their gustatory nerves or whether the nerve 

 fibers take the initiative and produce a bud on the surface, that 

 the evidence is much more in accord with the latter view. His 

 best proof is that the smaller subdivisions of the groups of taste- 

 buds are determined by the number of nerves supplying these 

 subdivisions, and that buds and nerves appear practically simul- 

 taneously. "The assumption . . . that the appearance of 



1 From the Department of Physiology and Physiological Chemistry, College 

 of Medicine, University of Illinois, Chicago, Illinois. 



465 



