Shhi.DON, Rcoriioiis to Chrinirdl St/t/iuh. 291 



fish after section of t\\c cord nvo duo, in all ])rol)al)ility, to a removal 

 of inhibition fi-oni ihc higher cenlci's, hy the nse of slioi'ter paths, or 

 to hoth. Pik(^ ('*'^j heliex'es that the second is the triu; explanation, 

 lie considers that norniallj the long paths by way of the brain are 

 made nse of. After section, pathways through the cord must serve, 

 giving a shorter arc which requires less time for the transmission of 

 the imi)nlses. This is sn])])orted by the conclnsions of jNIoore and 

 Oertel who suggest, however, that the higher centers nuiy have a regu- 

 latory rather than an inhibitory influence over the cord. Walton and 

 Paul think that the cord is particularly for active, instantaneous and 

 violent reflexes. It is prol)al>le that use of sliorter ])aths by the re- 

 flexes has much to do with the resnlt secured, but the evidence pre- 

 sented in the literature is strong in su])port of the view that the l)rain 

 possesses an influence over the cord of a regnlatorv ty])(>, at least. 



Wiping movements of the fins and finlets occur as in the normal 

 aninnd. This is in line with the results in the spinal frog and can not, 

 in either case, be considered purposeful, as Howell ('05) and Sher- 

 rington ('06b) clearly show. Such movements in a spinal animal 

 are simply such as are of a general protective nature for the normal 

 animal or else form a part of the habitual action of the organism. 



'No spinal shock was observed. This is as would be expected. 

 Steiner, Loeb, Bickel, and Bethe do not mention it for fishes. Moore 

 and Oertel show that it is slight in the frog and passes off quickly. 

 In mammals, as is well known from the work of Bastion ('90), Burns 

 ('93), Sherrington ('1)7, '00b), Senator ('98), Babak ('07) and Pike 

 ('08) the inflnence of shock is greatest. These citations fall in 

 line with the statement made above to the effect that the power of the 

 cord as an automatic center decreases as one ascends the animal scale. 

 Probably in the dogfish many of the reactions of the caudal part of 

 the animal take place normally through the cord, so'that section of it 

 brings about little change. 



Tlie Innervation and Bear I ions of ilie Xosfrih. — It will be noted 

 from the chart that the nostrils ai-e very sensiti\'e to the solutions 

 used as stimuli. The reactions obtained were also very decided. The 

 question arises as to whether these are due to the olfactory nerves or 

 the nerves of general sensation. Accordingly, different nerves were 



