52 THAUMANTIAS LUCIFERA. 
15. Thaumantias inconspicua, Forbes. 
Plate VIII, Fig. 3. 
A very delicate, and rather large species, measuring usually about three fourths of an 
inch across. Its umbrella is hemispherical, smooth, and colourless. The margin bears from 
sixteen to twenty colourless tentacles springing from pale yellow, inconspicuous bulbs, each 
tinged with a faint tawny spot. Between each pair there is a rudimentary marginal tubercle. 
The sub-umbrella is much more depressed than the umbrella; its opening is bordered by a 
rather broad veil. The ovaries are long and linear, and of a faint lilac or greenish hue, 
with a central fulvous line. They occupy more than half the course of each radiating vessel. 
The stomach is narrow, quadrangular, and of a yellow colour. It terminates in four lan- 
ceolate lips. The inconspicuous ocelli and pale reproductive glands easily distinguish this 
species from its congeners. It is common in the Hebrides. 
Plate VIII, fig. 3, a and 4, represent it magnified as seen from the side, and from above; 
3, ¢, is an ovary; 3, d, a portion of the margin, showing the tentacular bulbs, and the inter- 
mediate tubercles. 
16. Thaumantias lucifera, Forbes. 
Plate X, Fig. 2 (under the name of 7. lucida). 
This minute and curious Medusa is one of the most phosphorescent of all the naked-eyed 
species. Small as it is, I have not seen it more than one fifth of an inch across; it presents 
such very distinct characters, that I do not hesitate to describe and name it as a separate 
species, although specimens presenting truly adult characters have not as yet occurred. 
The umbrella is very much depressed, smooth, and transparent. The margin is fringed 
with a close-set series of tentacula, of which I reckoned no fewer than eighty-four (20 x 4-+-4) 
in several examples, but very small specimens had rather fewer of these organs. Their bases 
present a very minute ocellus, and there is a club-shaped, transparent organ, projecting, as it 
were, into the umbrella above it. This is probably the auditory vesicle in an early stage of 
development. The structure of the tentacles also indicates an immature condition of the 
tissues. The sub-umbrella is rather high in proportion to the umbrella. On its lower half 
are the four reproductive glands, sub-orbicular, lax, and yellow. The stomach is rather large, 
quadrangular, yellow, with imperfectly developed lips, whose margins are not fimbriated. 
I have met with this species in Zetland and the Hebrides, and in vast abundance off the 
Lizard Point, on the coast of Cornwall; also at Dartmouth, and in the west bay of Portland. 
When swimming, it carries its tentacula stiffly, and at nearly a right angle with the body. 
The Thaumantias plana of Sars (Beskrivelser og Jagtagelser, p. 28, pl. 5, fig. 13) bears a 
close resemblance to it, and is of the same size, but the tentacula are described as being more 
than one hundred in number. It is also evidently an immature species. The only other 
described form of Thawmantias with a depressed umbrella, and very numerous tentacles, is 
the 7. multicirrata of Sars (Op. cit. p. 26, pl. 5, fig. 12), but that has linear or clavate 
ovaries, more than 200 tentacles, and very few and distinct ocelli in proportion to the number 
