70 General Notes. 
important, perception of the deep tones did not seem to be wanting. 
The author regards Hensen's hypothesis as not proved, and inclines 
to the theory of Voltolini that each nerve fibre of the cochlea recog- 
nizes all tones. 
A Recent Study of *^ Rigor Mortis."— Some important work 
on rigor mortis has lately been done in the Physiological Institute 
at Konigsberg by Max Bierfreund, cand. med.^ Since the time of 
Nysten (1811) physiologists generally have suspected that the ner- 
vous system has some appreciable influence upon the time of appear- 
ance of rigor, and possibly upon its subsequent intensity. Munk, 
Bleuler and Lehmann, v. Eiselsberg, Tamassia, and others have in- 
vestigated the question and have come to quite contradictory conclu- 
sions. Tamassia asserts that rigor is completely independent of 
the nervous system, and supports this theory by the results of a 
number of experiments on frogs, sparrows, and guinea-pigs. A. v. 
Gendre, v. Eiselsberg, and now Max Bierfreund have, on the other 
hand, arrived at the opposite conclusion. Bierfreund has found in 
all the experiments performed by him decided evidence that some 
influence proceeds from the nervous system. "When he cut the 
sciatic nerve of a freshly-killed animal he found that rigor mortis 
always set in on that side 10-20 minutes later than in the muscles 
of the uninjured leg. This indicates that the nervous system 
exercises a quickening influence upon rigor, and this view is fully 
borne out by experiments upon the central nervous mechanism. 
Division of the lateral columns of the spinal cord or extirpation of 
one of the cerebral hemispheres will cause a delay in the appearance 
of rigor on the side which is dependent on the part removed. Bier- 
freund found, also, as might have been anticipated, that destruction 
of the central organs diminished the intensity of the rigor. 
The red muscles stiffen much later than tne white (11-15 hrs. as 
against 1-3 hrs.) ; and the time taken for completion of the rigor 
in the red muscles is much longer (52-58 hrs. as against 10-14 hrs.)- 
Bierfreund sees in this fact an explanation of the so-called law of 
Nysten that the muscles of the body fall into rigor in a fixed and 
definite order. He observed, for example, that in rabbits the muscles 
of the hind limbs, where white muscles predominate, invariably 
stiffen sooner than those of the fore limbs, where the muscles are 
exclusively red. 
High temperatures hasten the onset and the subsequent disap- 
pearance of rigor. Narcotics (chloroform and ether) if inhaled, 
delay it, but, if injected into the blood, produce a condition similar 
to rigor by their direct effect on the muscle substance. Chloral, 
which has no direct influence upon the muscle, effects a retardation 
of rigor when injected into the blood. Curare, according to von 
Eiselsberg and von Gendre, appears to destroy completely the influ- 
' Untersuchungen fiber die Todtenstarre, Pflliger's Archiv, Bd. XLlir.» 
