334 
(1934) in his study of the nematocysts of the 
coelenterates concluded from the figures of 
Viguier (1890) that Tetraplatia has a mono- 
cnidom of atrichous isorhizas and as such 
must be assigned to the Narcomedusae. Weill’s 
opinion seems to have been completely ac- 
cepted by Hyman (1940), and the trachyline 
affinities of this animal have been quite gen- 
erally accepted among those who have actually 
worked with the animal except for Dantan 
(1925) and Komai (1939). Komai concluded 
that Tetraplatia is a primitive scyphozoan, 
close to the Cubomedusae and Stauromedusae. 
The distribution of Tetraplatia , with the 
data included in the present report, is nearly 
world wide. The first Tetraplatia was taken in 
the Mediterranean Sea (Busch, 1851) and the 
next several reports of the animal were also 
from the Mediterranean concerning spec- 
imens taken at Messina. In 1885 Viguier re- 
ported finding specimens in the Bay of Algiers 
and his report of 1890 concerns the finding 
of these animals at that locality for five suc- 
cessive winters through a seasonal period 
from the end of December to the last of 
March and early April. Viguier was the first 
person to find Tetraplatia in large numbers 
and reported taking 200 specimens in a single 
net haul. Rose (1926) reported a single spec- 
imen from the Bay of Algiers. Carlgren (1909) 
extended the distribution of T. volitans to the 
neighborhood of the Chagos Islands in the 
Indian Ocean (4°5.8' S., 73°24.8' E.; 2°38.7 / 
S., 65°59.2' E.) and also reported the single 
known specimen of T. chuni from the begin- 
ning of the Benguela current off the west 
coast of Africa at 36°23.4' S., 17°38.1' E. 
Dantan (1927) in a brief summary of the 
distribution of T. volitans reported it from the 
type locality of T. chuni but this was appar- 
ently an error. The next extension of known 
range occurred when Leloup (1935) reported 
the discovery of eight specimens of T. volitans 
from seven net hauls of the "Meteor” samples 
from the Atlantic (stations 41, 166, 183, 184, 
216, 234, 278). These specimens ranged from 
17° N. to 29° S. in the eastern Atlantic and 
PACIFIC SCIENCE, VoL IX, July, 1955 
Fig. 1 . Tetraplatia volitans. The upper specimen 
shows a widely flaring mouth and presumably was in 
the process of engulfing food at the time of fixation. 
(Carbon drawings by Mrs. Lois Stone, Department of 
Zoology, University of California, Berkeley.) 
