54 
The Ohio Naturalist. 
[Vol. XIII, No. 3, 
Experiments witl: Phloroglucinol. 
From the position of the hydroxyl groups we expected to find 
that phloroglucinol caused greater effects than orcinol. In a 
scries of 20 experiments comprising 174 individuals we find that 
no retardation occurs, providing that oxidation by light is pre¬ 
vented. On the contrary, a slight acceleration of pigmentation 
takes place and the spots are almost invariably larger and more 
distinct throughout the entire course of development. Beyond 
this, and an apparent slight stimulation in growth, no effects have 
been noted. The drug was employed in a strength of 0.025%. 
Summary. 
By subjecting the eggs and larvae of Spelerpes bilineatus to the 
action of dilute solutions of tyrosin, orcinol, resorcinol and phloro¬ 
glucinol, we have observed the following effects on the general 
development, and in particular on the development of the pigment 
pattern: 
(1) . Tyrosin causes an acceleration of pigment development 
and later produces larvae which differ from the check by the 
absence of spots, and the presence of a much more dense deposi¬ 
tion of pigment. 
(2) . Orcinol, when applied for six or more days to embryos 
younger than the late neural groove causes monstrosities. When 
used with embryos at a later period of development it causes the 
body to become short and thick, the spots to become irregular or 
wholly absent, the entire color pattern to be blurred, the general 
character of the pigment pattern to be a coarse reticulation, the 
limbs to become “flippers”, and the larvae to be unable, or disin¬ 
clined, to take food. 
(3) . Resorcinol causes much the same modifications as orcinol, 
with the exception that the pigment reticulation is very much 
finer. A second resorcinol type does not show the abnormal 
body form. 
(4) . Phloroglucinol causes no abnormalities, and when any 
result is to be noted it is the more distinct markings of the color 
pattern and a slight acceleration of pigment development. 
(5) . All of these modifications are persistent for weeks after 
removal from contact with the drugs, and to all appearances the 
orcinol and resorcinol types would be permanent were it possible 
for the larvas to take food. 
The work is being continued. 
