‘Per MICROSCOPE. 
PUBLISHED ON THE 10TH OF Eacu Monts, 
At 25 Washington Avenue, Detroit, Mich. 
All articles for publication, books for review and exchanges should be addressed to 
the Editors of “THe Microscopr,”’ 25 Washington Ave., Detroit, Mich. 
Subscriptions, Advertisements, and all business matters, are attended to by THE 
Microscope PuBLISHING Co., 25 Washington Avenue, Detroit, Mich. 
All remittances promptly acknowledged. To insure answer, letters of inquiry, not 
intended for publication, must inclose a two cent stamp. 
Authors of papers will be supplied with 25 reprints free, when the desire for such is 
stated on the manuscript. 
Specimens for examination should be sent to the Microscope Laboratory, 25 Washington 
Avenue, Detroit, Michigan. In all cases the transportation charges on these specimens 
must be prepaid. 
Vou. IX. DETROIT, MARCH, 1889. No. 3 
ORIGINAL COMMUNICATIONS. 
ON THE EMISSION OF A COLORED FLUID AS A POSSI- 
BLE MEANS OF PROTECTION RESORTED 
TO BY MEDUS. 
J. WALTER FEWKES. 
N THE year 1880 I described* in the ectoderm of the covering- 
scales of a medusa belonging to the family of Agalmide, 
which was found at Villa Franca, Southern France, very peculiar 
pigment bodies, which discharge their contents into the surrounding 
water when the scales are broken from the axis of the animal. 
Since my description of these bodies no one seems to have 
studied them up to the present year (1888), when Dr. Bedot, in a: 
valuable paper on Agalma clausi, sp. nov., quotes my account, and 
again calls attention to these bodies. 
Since my observation was published, although I have studied 
many other genera of Physophores, I have found but one which 
exhibits this phenomenon of the discharge of coloring matter from 
its‘body when irritated. This is the genus Stephanomia (Forskalia 
auct.) which was observed to emit a similar coloring matter from its 
tasters. I can hardly doubt that in both cases we have a similar 
process which may possibly be a means of defense for the Physo- 
phore, which exhibits this peculiar phenomenon. My original des- 
cription of these colored glands on the covering-scales or bracts of 
Agalma is as follows : 
* Bull. Mus. Comp. Zool., Vol. VI, No.7. 
