G. ELECTRA. 
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Their substance is almost wholly membranous and 
flexible. Colour generally a deep brown. Their size 
never exceeds eight centimetres. The only species yet 
known belonging to this genus is often met with on the 
marine productions of the Mediterranean ; they are 
found attached to plants, polypidoms, and rocks. 
Pherusa tubulosa. Oblong, tubular, and pro- 
jecting cells, having their opening on one surface.— 
Plate 2. fig. 1. a. B. C. 
ELECTRA. 
Polypidoms branching ; cells oamparmlated, ci- 
liated on their border, and verticillated. 
This genus consists of but a single species, whose 
cells are verticillated round a pulpy centre, or adhere 
to some Thalassiophyte, usually cylindrical. The 
rings are in general so close as to make them appear 
imbricated. 
The Electra is very common in the European seas ; 
when the polypi are alive, their colour is a red-violet 
of greater or less brilliancy ; but when exposed to air 
and light, it becomes an earthy white. 
VERTICILLATE. 
Electra verticillata. Cells campanulated, ci- 
liated in their borders, and placed in rings one above 
the other. — Plate 2. fig. a. B. 2. 
European seas. 
