5 
developed gonophore is about 0.4 mm long (without the pedicel) 
by 0.25 mm wide. 
The ectoderm of the exumbrelia is densely set with nemato- 
cysts; these are found even in quite young stages (see below). 
The mesosarc is fairly thin. The four radial canals are narrow in 
the fully developed gonophore (PI. I, fig. 7), but broad and wide 
in younger stages (textfig. 3); they are connected by a narrow 
circular vessel. — Well-developed gonophores possess three long tent- 
acles with very large hollow bulbs. The filiform parts of the tent- 
acles are rolied up inside the beil cavity (see PI. I, figs. 6 and 7). 
Off the end of the fourth radial canal a slight swelling of the tis- 
sues may be discerned, indicating a fourth 
tentacular bulb. There is a narrow but well 
developed velum (PI. I, fig. 7). — The man- 
ubrium is circular or somewhat quadrang- 
ular in cross-section; it has a thin ecto- 
dermal epithelium, in which I have not been 
able to find genital cells. The most inter- 
esting feature of the gonophore is, however, 
that the four perradial edges of the manu- 
brium are confluent with the radial canals, 
forming four perradial “mesenteries” separ- 
ating four interradial pouches between the 
manubrium and the subumbrella. The long¬ 
itudinal section (PI. I, fig. 7) has passed along a radial canal on 
the left hånd side, whereas to the right it has passed one of the 
interradial pouches. The tentacular bulb on this side has been hit 
near the middle, but the section has gone clear of the radial canal 
and the mesenterium. The cross-section (textfig. 3) exhibits a younger 
stage with wide radial canals separated by interradial pouches of 
about the same width. The pouches may be traced almost to the 
very bottom of the body. 
There can be no doubt but that the gonophores of this species 
develop into free medusæ. In the most advanced stages observed 
the gonophore has lost its organic connection with the stolon, but 
is still enclosed within the unbroken perisarc. The specimen figured 
in PI. I, fig. 6 is connected with the stolon by a very thin and 
Fig. 3. — Transverse section 
of a gonophore. — ex. ex¬ 
umbrelia; man. manubrium; 
r.c. radial canal; ir.p. inter¬ 
radial pouch of the beil 
cavity. 
