46 THAUMANTIAS GLOBOSA. 
transparent, and smooth. Around its margin are ranged in close order more than 200 
fine colourless tentacula, rmged and granulated, when highly magnified. At the base of each 
is a very small but very black and well-defined ocellus. Round the inner margin of the 
umbrella is a rather wide veil, which, instead of being borne horizontally in all the specimens 
I met, was lax and dependent. The sub-umbrella is hemispherical, and divided into four equal 
portions by the four radiating vessels, which traverse through the greater part of their courses - 
four long, clavate, yellow, rather narrow, reproductive glands. I have represented an 
appearance presented by one of these glands, as if of a much contorted tube within it. This 
is probably of the male sex. From the centre of the sub-umbrella hangs the short and 
very broad stomach, opening by four large, triangular, fimbriated lips. It is usually pale, 
sometimes slightly tinged with yellow. 
The umbrella of this species was often more than half an inch in breadth, and of the 
same height. It has hitherto occurred only in the Zetland seas, and is not very common there. 
Plate X, f, 3, a, represents the entire animal magnified; 3, 6, the stomach and lips ; 
3, ¢, one of the reproductive glands, and some of the marginal tentacula (contracted), with 
their ocelli; 3, d, one of the tentacula magnified when in extension. 
7. Thaumantias globosa, Forbes. 
Plate X, Fig. 4. 
Umbrella globular, smooth, transparent, colourless, delicate. Margin with a rather close- 
set fringe of tentacula. These are tinted with purplish-yellow, and when magnified, present 
a ringed and granulated aspect. They are highly contractile, and very slender. They spring 
from reniform tubercles of a pale yellow colour, with a crescentic ocellus formed of tawny 
pigment-cells, inclosing a cavity in which a vibrating mass of otolites is plainly seen. The 
tentacular bulbs are very large in proportion to the diameter of the tentacles. ‘The sub- 
umbrella is small as compared with the body; it is intersected by the four radiating vessels, 
which traverse in that part of their course nearest the margin four lax, more or less reniform, 
reproductive glands, firmer and more defined in form, being ovate, in the females. They are 
pale yellow in the males, tinged with tawny in the females. The gastric vessels present a 
knob-like enlargement at the point of their union with the marginal vessels. Here and there 
among the tentacles are little colourless tubercles studding the margin. The number of the 
former in a large specimen was 7 x4-++4; in a small one 3xX4+4. They evidently increase 
with age. The stomach is very short, of a pale yellow colour, and bordered by four lanceolate 
furbelowed lips. The umbrella, in well-grown specimens, measures about half an inch across. 
This delicate species is very abundant in the harbours of both sides of the Zetland Isles, 
usually in company with Thaumantias hemispherica and T. pilosella. It has a remarkable 
habit of crumpling up, as it were, its tentacula into a confused mass. When very young, as 
represented at fig. 4, ¢, of plate X, it often extends its tentacles to a great length, and the 
reproductive glands appear of disproportionate size. Plate X, fig.4, a and 4, represent its adult 
state, magnified ; 4, d, is the stomach and lips; 4, e, the reproductive gland of a male; 4,7, 
an ovary full of eggs; 4, g, a quarter of the margin, with the tentacular bulbs; 4, 2 (marked 
e by mistake in the plate), a tentacle-bulb greatly magnified, showing the ocellus, the otolitic 
capsule, and the structure of the tentacle. 
