758 Proceedings of Royal Society of Edinburgh. [sess. 
Sarsia tubulosa (Sars). (Table II. 10.) 
Oceania tubulosa , Sars, 1835, p. 25, pi. v. fig. 11. 
Sarsia macrorhyncha , Busch, 1851, p. 10, taf. iii. figs. 7-10; 
taf. iv. figs. 1-2. 
In 1902, it appeared at the beginning of April and disappeared 
at the end of June. Adults and also some early stages were 
taken at the end of April. 
Sarsia pulchella :, found by Allman at Rothesay, probably belongs 
to this species. 
Thamnitis, nova species 1 (Table I. 24.) 
Generic character. — Margelidse with branched oral tentacles 
and four single perradial tentacles. (Haeckel, 1879.) 
In 1901, two specimens of an early stage were taken, — one on 
21st September' and the other on 8th October. 
Description of the specimen taken on 8th October : — The 
umbrella is bell-shaped, with thin walls ; the ex-umbrella 
has a few nematocysts scattered over its surface. Yelum very 
broad. The stomach is cone-shaped, with a quadrangular base, 
and is about half as long as the cavity of the umbrella. Four oral 
tentacles, which are fairly long and once dichotomously divided, 
and terminate with very small knobs containing nematocysts. The 
gonads have not yet begun to develop. Four perradial marginal 
tentacles, which are rather short and thin, and have cone-shaped 
basal bulbs. Ocelli are absent. 
Colour. — Stomach yellowish-brown. Basal bulbs of an orange 
colour. 
Size. — Umbrella about 1 mm. in length and width. 
The specimen is, without doubt, an early stage, as the gonads 
have not yet begun to develop. There is also an apical stalk, over 
the base of the stomach. This stalk is the rudimentary remains of 
the canal by which the medusa was connected with its hydroid. 
It is frequently present in very early stages, but soon disappears 
by absorption. 
The medusa was placed in a plunger bell-jar, kept there for six 
days, and then preserved. During the six days the oral tentacles 
developed another branch. 
Description of the specimen taken on 21st September : — 
