Gland-Cells of Internal Secretion in Spinal Cord of Skates. 15 
vascular and richly supplied with nerves. Groups of sympathetic 
nerve-cells are occasionally found both in the medulla and in the deeper 
parts of the cortex. The substance adrenaline is secreted by the cells 
of the medulla. It acts as a powerful local styptic, raises blood pres- 
sure, and stimulates the heart. Injected subcutaneously it causes 
relaxation of muscles of the bronchioles; injected intravenously it 
causes glycosuria; in minute doses it causes checking of the rhythmic 
peristalsis of the intestine. It causes contraction of the uterus (non- 
pregnant) of the cat. In general, it acts especially on all functions in- 
nervated by the sympathetic system. 
It was stated above that the cells of the medulla which secreted 
adrenaline were characterized by the chromophil reaction when treated 
with chromic acid. It is interesting to note that chromophil cells have 
been found in almost all vertebrates, even in Petromyzon; also in the 
mantle of the mollusk Purpura and in ganglion nerve-cells of annelids 
and crustaceans. The function of the chromophil cells always appears 
to be the same. 
It was thought that the large cells of the skate spinal cord might be 
of this nature and that their sceretion might possibly be something 
allied to adrenaline. Accordingly the following experiments were tried: 
Pieces of the spinal cord of Raia levis were placed in Miiller’s fluid 
for two months. Upon sectioning, it was found that these large cells 
did not give a decided chromophil reaction. 
Spaeth has shown that adrenaline will cause contraction of chroma- 
tophores, and that this reaction will be produced even when the adrena- 
line is diluted with water as much as 1 : 1,000,000. Fresh spinal cords 
from Raia ocellata were ground up and a sea-water extract prepared. 
Seales of Fundulus showing well-expanded chromatophores were im- 
mersed in this extract. The chromatophores were watched under the 
microscope. No contraction occurred. 
Vulpian showed that adrenaline was readily oxidized by various re- 
agents, giving characteristic color reactions with ferric chloride, chlo- 
rine water, and caustic alkalies. Addition of a sea-water extract of 
skate spinal cord to each of these caused no color changes. 
Attempts were also made to discover the effects upon the blood pres- 
sure of the skate of an extract of the region of the spinal cord containing 
these large cells, but owing to the difficult technic involved in obtaining 
blood-pressure records from the skate no satisfactory results were 
obtained. The experiments given above are sufficient, however, to 
indicate strongly that these cells of the skate produce nothing that is 
allied to adrenaline. 
Whatever the nature of the granules may be, their presence, together 
with the vacuoles and precipitate in the cells, fits in well with the hy- 
pothesis that these cells are glands of internal secretion. Vacuolation 
and partial liquefaction of the cell, followed by the formation, growth, 
