The tiny Sarsia has but four tentacles, which spring from as many
equidistant points on the margin of the bell. But in the genus
_Æquorea_, of the same family, these organs are far more numerous,
two species which I first discovered at Ilfracombe having, the one
thirty-six, the other about two hundred tentacles. The former of these,
which I have honoured with the name of the late Edward Forbes,[129]
differs much in general appearance from the little Sarsia, being a
cake-shaped segment of a globe, about three or four inches in diameter,
and an inch and a half in thickness. The roof of the interior is low
and nearly flat, or indeed dropping slightly in the centre.
[Illustration: