108 



SCIENCE. 



[N. S. Vol. VIII. No. 186. 



Dk. Geoec4 Kaesten, decent in botany in 

 Kiel, Dr. Richard Abegg, docent in physical 

 chemistry at Gottingen, and Dr. Bohming, 

 docent in zoology at Gratz, have been promoted 

 to associate professorships. Dr. Eeitzenstein 

 has qualified as docent in chemistry at Wiirz- 

 burg and Dr. Simon as docent in physics in 

 Gottingen. 



DISCUSSION AND CORRESPONDENCE. 



SUBSTITUTIONAL NERVOUS CONNECTION. 



In a series of recent papers the writer has en- 

 deavored to show that the idea now apparently 

 dominant that, with the single exception of the 

 olfactory, the peripheral nervous connections 

 are indirect rather than direct is an unwarrant- 

 able assumption. It has been found possible to 

 demonstrate in the skin termini of nerves which 

 are, so far as can be seen, unimpeachable in- 

 stances of connection by continuity. These are 

 then of the same nature as the connections of 

 the olfactory cells with the fibres of the olfac- 

 tory nerve. On the other hand, it appears that 

 some of the most careful observers have de- 

 tected similar rod-cells with special nervous 

 functions which are only in indirect communi- 

 cation with the nerve which conveys the stim- 

 ulus. If it could be shown that the sensory 

 cells are uniformly without nervous processes 

 it might be assumed that they constitute by 

 themselves a special class of nervous organs 

 which normally do not acquire the neurite, but 

 the admitted existence of such a process of the 

 olfactory cells and the fact that these cells 

 are otherwise so similar to the other instances 

 of nervous endings, in which it seems to be 

 proved that this sort of direct connection is ab- 

 sent, prevents the possibility of establishing 

 such an independent class of structures. Still 

 more, if our own observations are taken into 

 account, it seems necessary to oiFer some other 

 suggestion to account for the discrepancy in this 

 particular. Take, for illustration, the case of 

 the organs of taste, which, in spite of their evi- 

 dent resemblance to the olfactory termini, are 

 generally stated to have only indirect nervous 

 connections. I have elsewhere suggested the 

 possibility that in the case of these sense organs 

 the original proton is to be found in the same 

 paired bands of cells from which the olfactory 



epithelium is derived. It is admitted that to 

 these other elements have possibly been added 

 by way of the gill clefts, but it seems only natural 

 to suppose that the palatal portion, at any rate, 

 may have had the origin suggested. If this 

 were so, it is evident that there is no relation be- 

 tween the position of the peripheral proton and 

 the source of the nerves supplying these organs. 

 It might be suggested, therefore, that the origi- 

 nal nervous communication having been lost, 

 the new connection has been established in a 

 secondary manner by the apposition of what at 

 one time were free termini between the cells 

 to these specialized cells. If the illustration 

 chosen appears far-fetched, a more general illus- 

 tration will indicate still more clearly the ap- 

 plication of theory proposed. There can be no 

 doubt that, on any theory of evolution of the 

 higher vertebrates from the lower, a difficulty 

 arises in the attempt to construe the fact that 

 the lateral line organs with their homologues 

 and allies do not seem to obey a constant law 

 of nervous supply, while in the higher verte- 

 brates it is difficult to follow the transforma- 

 tions which these organs have undergone. It 

 is possible that these diflticulties will largely 

 disappear if the probability be admitted that, 

 in the course of evolution, the original connec- 

 tions have been lost or diverted and that new 

 ones have then been established by the applica- 

 tion of some of the free nerve endings to the 

 cells thus deprived of their original nervous 

 connections. That some such changes have 

 taken place seems to the writer more than prob- 

 able. If this be admitted, it is not to be won- 

 dered at that in the lower vertebrates especially 

 the two sorts of endings may be encountered 

 side by side in diflerent parts of the skin. It 

 is not the present intention to enlarge on or 

 illustrate this thought, which is thrown out in 

 the hope that the suggestion taay prove fruitful 

 in the hands of others. 



C. L. Heeeick. 

 University op New Mexico. 



the exhibition of cetaceans by papiee 



mache casts. 

 To THE Editor of Science : Mr. F. A. Lu- 

 cas calls my attention to the following passage 

 in an editorial notice of the new Cetacea Gal- 



