388 



Transactions. 



Tentacles. — These are conical in form, tapering to a fine point, and reduc- 

 ible to thin filaments. In colour they are white, with brown markings. Each 

 has a brown tip. They are arranged very evenly in four cycles, the inner 

 two nearly equal. Each of these two contains 6 tentacles ; the third contains 

 12 slightly shorter ; the fourth contains 24, shorter still. The ectodermal 

 muscles are strong, and are borne on long processes of the mesogloea. The 

 mesogloea is very fibrous, and contains a large number of nuclei. There are 

 numerous nematocysts. 



Oral Disc. — The disc is white, mth a sUght brownish tinge. Some 

 specimens have radiating brownish lines. There is a pair of opaque-white 



lines radiating from the siphonoglyphs to 

 the edge of the disc. The mouth is some- 

 what depressed, and the siphonoglyphs are 

 not prominent. The stomodaeum is not 

 readily everted. The histological characters 

 of the disc closely resemble those of the 

 tentacles. 



Sphincter Mxiscle. — This is mesogloeal in 

 character, consisting of a thickening of the 

 mesogloea in the upper part of the column, 

 the thickened portion containing numerous 

 muscle-spaces. The whole mesogloea of the 

 wall is muscular, producing, no doubt, the 

 strong contraction which is so characteristic 

 of the animal. 



Mesenteries. — There are 32 to 36 pairs, 

 2 pairs being directives. The musculature 

 is very strong, the muscle-banners appear- 

 ing as great rounded masses, but slightly 

 attached to the mesentery (fig. 11). 



Gonads. — The mesenteries are all fertile, 



except the directives. All the animals 



sectioned happened to be females, and all 



showed remarkable fertility. Ova appeared 



at nearly all stages. At first they occupy a 



position imbedded in the mesogloea (fig. 11). 



but as they advance in maturity they form 



ereat masses, almost filling the intermesen- 



terial spaces (Plate XXIV. fig. 1). Finally 



they may become detached 



^ii>^ from the mesenteries and 



form globular masses, 



showing in cross - sections 



as rounded discs 



(Plate XXVjI-). 



bryos were seen. 



Habits. — All my speci- 

 mens were found in dark 

 Fig- 11- places, never more than 



four in one place, usually single specim ns. The species seems rather 

 uncommon. 



Dimensions. — .2-18 mm. in diameter, 25-45 mm. in height. 



or rings 

 No em- 



