680 General Notes. 
but has only ten thousand times as many muscle fibers, each a 
hundred times longer than those of the dwarf, who thus takes one 
hundred skips while the giant takes one. The same physical laws 
apply to all muscles, so that, when all the factors are considered, 
muscles of the same quality have equal power.— W. N. Lockington. 
THE DIRECT INFLUENCE OF GRADUAL VARIATIONS OF TEMPERA- 
TURE UPON THE RATE OF BEAT OF THE Doc's Heart.—In the 
Proceedings of the Royal Society, Professor Martin, of Johns 
Hopkins University, describes his researches upon the effect: 
changing temperatures upon the rate of beat of the dog's heart 
The heart was perfectly severed from all physiological connection 
with the rest of body, with the exception of the lungs, and was 
nourished by an artificial stream of whipped blood. “As the re- 
sult of many experiments it was found (1) that the isolated dogs 
heart beats quicker when supplied with warm blood, and slower 
when cold bloodis supplied to it; (2) that the rateof beat depends 
much more upon the temperature of the blood in the coronary 
arteries than on its temperature in the right auricle or ventricle; 
(3) that when defibrinated calf’s blood is used to feed the heart, 
that organ cannot be kept alive as long as when defibrinated dog’ s 
blood is employed; (4) that no matter how long an experiment 
lasts, the defibrinated blood, circulated again and again through 
the heart and Jungs, shows no tendency to-clot ; hence fibrinozen 
is not produced in those organs. 
The question answered by the first of t 
one for whose solution the research was undertaken. The exper : 
xtrinsic mee Z 
ts sh i i its highly developed e Be 
ments show that, in spite of its highly develop s, so far as 
he above results was the 
rhythm is concerned, in its own nerve-muscular tissues, a 4 : 
iati ithin wide limits (42°-27, ©) J 
to temperature variations within wide (4 To account 
the frog’s heart or that of the embryo chick does. k 
for the quick pulse of fever we, therefore, need ot 
beyond the mammalian heart itself: we require no excita- 
tion of accelerator cardio-extrinsic nerve-centers. 
Skin Viston.—In a recent communication to the Vee . 
emy, Professor Graber, of Czernowitz, describes a long te affone 
experiments with regard to the “ skin-vision” of anima d of vis- 
ing exact proof that certain animals, without te qualita- 
ual organs proper, can make not only quantitative hiefly tothe 
tive distinctions of light. These experiments relate c tic) lower 
earthworm as representing the eyeless (or “ derma ee 
animals, and to the Triton cristatus, as representative poets ae 
(“ ophthalmoptic”) eyed animals. In a table Pro oa ee 
presents columns of numerical “ ccefficients of rea! ce illumin- 
cating how many times more strongly frequented a SPAC "=. th 
ated with bright red, green or white without ul 
