EASTERN COAST OF THE UNITED STATES. 



33 



ance ; often brought together and spirally twisted in a central bundle. Base with a small 

 but distinct opening. 



Color of column dark cinnamon-brown, lined longitudinally with a lighter tint of the 

 same ; outer tentacles cinnamon-brown, lighter at the bases ; inner series darker, marked 

 with white longitudinal lines ; disk bright yellow, the central portion brown ; at the bases 

 of the tentacles spotted with dark brown. 



Length of the largest specimen in expansion, 24 to 28 inches; diameter at disk,1.50 ; 

 at centre of body, 1 inch. (Coll. Mus. Comp. Zool.) 



Charleston, S. C, buried to the tentacles in mud at low water (H. J. Clark, Wm. Stimp- 

 son, L. Agassiz) ; Beaufort, N. Carolina ( Wm. Stimpson). 



The description of this very interesting species has been drawn chiefly from a beautiful 

 series of drawings in the possession of Prof. Agassiz, made from life by Mr. Burkhardt. It 

 is remarkable for its great size and fine colors. 



Genus Arachnactis Sars. 



ArachnacUs Sars, Fauna Littoralis Norvegise, i. (1846). Arachnactis Gosse, Actinologia 

 Britannica, p. 263 (1860). 



Column of moderate length, elliptical or subcylindrical, rounded at the base, apparently 

 destitute of a terminal opening ; surface smooth, in the British species said to be capable 

 of adhering. Tentacles few in number, not contractile, the marginal ones long and slen- 

 der ; those of the inner circle short and thick, corresponding in number with the others. 

 The development of new tentacles in each circle takes place in pairs at one extremity of 

 the anterio-posterior diameter in a bilateral manner. The species swim freely in the sea 

 with the tentacles downward. 



Arachnactis braehiolata A. Agassiz. 



Arachnactis braehiolata A. Agassiz, Proceedings of the Boston Society ofNatural History, ix. p. 159 (1862) ; Journal of the Bos- 

 ton Society of Natural History, vii. p. 525 (1863). 



Body strongly compressed in the plane of the anterio-posterior diameter, rounded at 

 the base, and in all the individuals observed somewhat enlarged. The outer tentacles ex- 

 ceed the column in length ; the inner are, in the specimens described, very short, conical, 

 generally carried erect. 



Color of body pale ochreous, diaphanous ; the lamellae appearing through the walls 

 like darker lines. 



Massachusetts Bay, swimming by night near the surface ; very abundant about the first 

 of September (A. Agassiz). 



This species has as yet been observed only in the young state. It was then about an 

 eighth of an inch in length, and had sixteen tentacles. It still retained some of the yolk 

 mass at the base, and moved chiefly by cilioe covering the surface, swimming in an oblique 

 position, the largest tentacles hanging downwards. 



For a more detailed account of this interesting form I would refer to the original papers 

 by Mr. Agassiz. 



MEMOIRS BOST. SOC. NAT. HIST. Vol. I. 



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