IQIO. | J. Rrrcwre: Hydroids of the Indian Museum. yi 
fig. I) a single joint traverses the stalk, but this is due to fracture 
and subsequent regeneration ; in normal specimens no joint occurs, 
and only a delicate film separates the cavity of the hydrotheca 
from the common cavity of the colony. The hydranth has about 
6 to 8 tentacles. 
Gonosome.—The gonangia are borne on short and indefinite 
stalks, and are at least three times as large as a hydrotheca. They 
are roughly cylindrical in shape, and have walls circled by faint and 
irregular corrugations. In the earlier stages of development an 
opercular plate (‘‘ deckenplatte’’) at the end of the blastostyle, 
closes in the top of the gonangium, but, as development proceeds, 
this disappears and the perisare folds outwards, forming a gracefully 
everted margin. ‘The developing medusz, three in number in each 
gonangium, are roughly spherical, but the state of preservation 
was so imperfect that details could not be observed. The manu- 
brium is large, and four stout tentacles are present cre the medusa 
is set free. 
Measurements. 
Hydrotheca, length ee 2 0°36—o°39 mm. 
diameter at mouth A o'18—o'2I_,, 
sonangium, length .. ef. ai l'OI—1I'23_,,; 
a maximum diameter... 0°36—0'43 so, 
From Hebella calcarata (A. Agassiz), which it approaches, 
this species differs in its hydrauth, which has only seven instead of 
about sixteen tentacles, and in its hydrotheca, which has neither the 
cylindrical shape nor the marked bulging towards the base character- 
istic of the other species, and which, moreover, shows no traces of a 
strong chitinous septum at the base. From H. lata, Pictet (1893, 
p. 40, pl. ii, figs. 34, 35), it is distinguished by having fewer tentacles, 
by its much smaller size, and by the more obconical shape and 
everted margin of its hydrotheca. 
Locatiry: Growing on Lytocarpus pheniceus, dredged 8 miles 
west of Interview Island, Andaman Islands, depth 270—45 
fathoms. 
Tvpe in the Indian Museum, Calcutta. 
Thyroscyvphus vitiensis, Marktanner-Turneretscher. 
Markt-Turner., G., 1890, p. 210, pl. iii, fig. To. 
Two small fragments which appear to me to represent this 
species occurred with other odd colonies from the Andamans. They 
are only 12 mm. high, portions of young colonies, but even so they 
show considerable variation in the length and diameter of the inter- 
nodes. In one fragment, which is strongly geniculate, they are 
from 1°5 to r-9mm. long, and 0715 mm. in diameter ; in the other, 
while the length remains similar, the diameter is 032mm. The 
hydrothecze measure from 0°98 to 1°12 mm. in height, and 0°66 mm. 
in diameter at the mouth, ‘The hydranths, which are exceedingly 
dumpy when contracted, appear to have about 26 to 30 tentacles. 
’ 
