THE FORBESIAN .^QUOREA. 345 



On examination the larger flattened ones resolved 

 themselves into two species. One was the colourless 

 frosted Mquorea that I had obtained before, several 

 specimens of which appeared in no wise to differ from 

 the former. But the majority of individuals now cast 

 ashore were of a much larger and finer species of the 

 same genus. (See Plate XXIV). 



It differs from the former species in the following 

 particulars. It is much larger, being from two to three 

 inches in diameter, but lower in proportion, being 

 about \\ inch in height, and resembling a cake or 

 bun in shape. The umbrella is smooth, clear, and 

 apparently colourless; but when viewed sidewise> 

 against a dark back-ground, the rays of light that 

 pass through the whole diameter of the umbrella are 

 tinged of the most brilliant azure blue, which colour 

 prevails for about a quarter of an inch above the sum- 

 mit of the sub -umbrella, and is then gradually lost, 

 doubtless by the rapid diminution of the thickness of 

 substance through which the rays are transmitted. 



The sub-umbrella is very low and depressed, about 

 \ inch in height : its substance is colourless, but the 

 radiating vessels that traverse it, and which were 

 frosted in the former species, are here of a delicate 

 rosy hue, which is the colour also of the dependent 

 margin of the central circle that occupies the placer of 

 a peduncle. They are fewer (about 65 or 70 in all) 

 and more slender, than in M. vitrina. 



The sides of this circle are cut into four triangular 

 lobes of membrane (more or less developed), which 

 are fringed with dehcate attenuated pink filaments, 

 depending and floating freely in the water. The 



