THE 
AMERICAN NATURALIST. 
VoL. xiv. — SEPTEMBER, 1880. — No. 9. 
THE SIPHONOPHORES. 
I.—THE ANATOMY AND DEVELOPMENT OF AGALMA. 
BY J. WALTER FEWKES. ; 
4 s tubular jelly fishes present very interesting conditions of 
life, and so little has been written about them, except in spe- 
cial scientific memoirs, that a popular account of the anatomy 
and embryology of a few typical forms may be interesting to 
those who have not access to the literature. The scientific name 
of these animals is Siphonophore ; they are all marine and found 
in almost every latitude, although most abundant in tropical 
oceans, ; 
The best known example of the Siphonophore is by no means 
the best adapted to give a general idea of the structure of the 
order. The most common representative in our waters is called 
by sailors the “ Portuguese man-of-war.” Its scientific name is 
Physalia, and figures of it appear in almost every text book on 
zoology. The animal, however, is badly chosen to represent the 
order, for it is widely different in structure from the other tubular 
jelly fishes, and not only does not have a tube-like body, the 
characteristic which has suggested the name of the order, but 
so its anatomy and development, as far as known, are both 
abnormal and present many difficulties to one who wishes a 
knowledge of those jelly fishes with which it has a kinship. 
If one should be asked to choose the genus best calculated to 
give a good idea of a tubular jelly fish, I think he would find one 
of the Agalmidz the best choice. Two genera belonging to this 
VOL. XIV,—No. Ix. - 
