1904 — 5 .] Report on Medusae found in Firth of Clyde. 749 
top. The velum is moderately broad. The stomach is large, 
cylindrical in shape, having its base composed of a cellular 
tissue. The mouth is small, circular in shape, and its margin is 
lined with nematocysts. The length of the manubrium is about 
half to two-thirds the length of the cavity of the umbrella. There 
are four fairly broad radial canals and a circular canal. The 
gonad completely surrounds the stomach, forming a large swelling. 
The four tentacles are of equal length, one opposite each radial 
canal, and have transverse circular bands of nematocysts. The 
basal bulb of a tentacle is broad, somewhat triangular in shape, 
and is without an ocellus. 
Size. — Umbrella 3 mm. in length and 2*5 in width. 
Colour. — A dark brownish transverse band of pigment near the 
base of the stomach (conspicuous in one specimen, but very faint 
in the other). A circular band of dull carmine pigment just above 
the mouth. Basal bulbs of the tentacles of a dark brownish 
colour. 
There is only one species in the British seas. The medusa can 
be easily distinguished from a Sarsia by the presence of the eight 
longitudinal rows of nematocysts upon the ex-umbrella and by the 
absence of ocelli. The hydroid Ectopleura dumortieri (van 
Beneden) has not yet been recorded for the Clyde. 
Euphysa aurata, Forbes. (Tables I. 8 ; II. 12.) 
Euphysa aurata , Forbes, 1848, p. 71, pi xiii. 
In 1901, it was first seen near the end of May, but was absent 
during June. On 20th July it was common. Very scarce during 
September, and occasionally taken during October. Two specimens 
were taken on 16th November. 
In 1902, a large specimen with immature gonads was taken on 
24th January. There can be but little doubt that this medusa 
was born in 1901. During February, March and April not a 
single specimen of Euphysa was seen. It was not until 15th May 
that Euphysa began to appear, and after this date it was usually 
present in the nets until 22nd October. From 11th June to 
4th August it was fairly common, but was very scarce from the 
middle of August to nearly the end of October. Early stages occurred 
in June and July. Adults were taken during July, August and 
