126 
THE OCEAN WORLD. 
indeed, when they make their appearance in the cases of our natural 
history collections. 
The Fan Gorgon, from the Antilles (Fig. 42), is a species which 
often attains the height of eighteen or twenty 
inches, and nearly as much in breadth. The 
net-work of its interstices with its unequal 
and serried meshes, resembling fine lace, have 
led to its designation of Sea Fan. Its colour 
is yellow or reddish. In Fig. 43 we have 
the Fan Gorgon magnified to twice its natu- 
ral size, showing the curious details of its 
organization. 
The Whorled Gorgon (G. verticellata), 
which is found in the Mediterranean, is yel- 
lowish in colour, and also of elegant form. It 
is sometimes called the Sea Pen. This 
species is represented in Fig. 44, while 
Fig. 45 represents a small branch magni- 
fied four times, in order to give an exact 
idea of its form. 
The Gorgons are not known to he useful 
either in the arts or in medicine. They 
are ornamental in cabinets, and interesting both as objects ol stud} 
and of zoological curiosity. 
IsiDIANS. 
The Isidas constitute an intermediate group between the Gorgons 
and Corallines. Their polypier is arborescent, hut its axis is formed 
of articulations alternately calcareous and horny. The principal genus 
is that of the Isis, which is met -with in the Indian Ocean, on 
the American coast, and in Oceania. The inhabitants of the Mo- 
lucca Islands use these animals medicinally as a remedy in certain 
diseases ; but as they use them for the most opposite maladies, it may 
he doubted if they are really efficacious in any medicinal point of 
view. 
The Isis corolloidis of Oceania has a polypier with numerous 
slender branches, furnished with cylindrical knots at intervals, con- 
tracted towards the middle, finely striated, and rose-coloured. Is*® 
Fig. 45. Gorgonia verticellata 
(Pallas), magnified four times. 
