92 
CLASS L— ORDER II. 
GELATINOUS. 
8. Laomedea gelatinosa. Cells campanulated ; 
border elegantly crenated ; branches, both principal 
and secondary, numerous and dispersed. 
Coast of Belgium. 
PRICKLY. 
9. Laoebieda muricata. Stem articulated; cells 
peduncled, alternate and solitary on each articula- 
tion ; ovaria peduncled, prickly, and placed on the 
tubes of the root. 
Coast of Scotland. 
THOA. 
Plant-like and branching ; stem formed of nume- 
rous interwoven tubes ; cells few; ovaria irregularly 
oval ; polypi projecting. 
These Polypidoms have characters peculiar to them, 
but also many irregularities, principally among those 
which are come to their full growth ; in this last state 
they resemble a root of a stiff and horny substance, 
brittle in the lower part, a little flexible in the upper, 
and garnished with a large quantity of straight, short, 
stiff fibres. 
The substance of the Thoas is horny, membranous, 
and rather brittle. 
Their colour is a fawn, more or less deep, some- 
times dull, at others bright and shining. 
They seldom rise beyond two decimetres, and ad- 
