﻿April, 1857.] 



ELLIOTT SOCIETY. 



137 



principal colors in these Medusas — yellow and red. There are 

 different shades of these — but the digestive cavity is nearly always 

 red or orange colored, or red within and slightly yellow without. 

 The same is true of the tentacular bulbs and of the clavate ex- 

 tremities of the tentacula in such genera as have them. Blue is 

 found among the Siphonophoras, and is said to tint the transparent 

 disks of some iEquorece. But in this latter case as in that where by 

 reflected light a green tint is given to the sexual organs of Tima, 

 the color does not appear to be due to pigment cells. In fact color 

 among these animals is very uniform, belonging not so much to 

 ornamentation as to a connection with the functions of essential 

 organs, and therefore hardly enters ordinarily into specific char- 

 acter as an important element. The peculiar tone and disposition 

 of color might more safely be assumed as a source of generic than 

 of specific character. 



SARSIA. Lesson. 1843. 

 Syn. Sthenyo Dujardin, Ann. Sci. Nat. 3ieme. Ser. vol. 4, p. 275. (1845.) 



General form more or less deeply campanulate. Digestive 

 trunk, long, cylindrical tubiform, separated by a constriction from 

 the intersection of the radiate tubes, where there is a small quad- 

 rate chamber. Sexual organ investing the digestive trunk; four 

 radiate tubes forming four sinus-like enlargements at the four 

 marginal bulbs, each of which bears an ocellus at its upper part, 

 while from its lower springs a contractile, filiform, nodose tentacu- 

 lum, which is tubular (?). 



The larva is coryne (Syncoryna, Ehrenberg.) The medusa 

 is developed among the tentacula, or immediately below them. 

 In the course of development the disk is involute, and the ten- 

 tacula first appear within it, at least in the species of Boston 

 harbor. 



Remark. — Forbes makes no mention whether the tentacula of 

 his four Sarsise are tubular or not. Dujardin is similarly silent 

 with respect to Sthenyo. Sarsia mirabilis of Boston harbor is 

 known to possess tubular tentacula. The condition of Gegen- 

 baur's Oceania thelostyla is, in this respect, also unknown, while 

 in the following species I have as yet not been able to observe 

 any canal in the tentaculum. The Sarsias of the Northern shores 

 of Europe must be the true Sarsise, and since such a difference as 

 that of solid and tubular tentacula would be of generic value, the 

 question merits attention, and can only be settled by an examina- 

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