BY R. VON LENDENFELD, PH.D. 305 



Rhizostonia leptocephalus. De Blainville, 1834. Actinologie, 

 p. 298. 



Umbrella semi-spherical, with 48 marginal flaps. In each 

 Octant 4 rectangular velar flaps between 2 small ocular flaps (?). 

 Subgenital ostia twice as broad as the pillars between ; the mouth 

 cross smooth. Arms very long and thin, ribbon-shaped, about 

 twice as long as the diameter of the Umbrella, with a bundle of frills, 

 at the end from which there protrudes a pointed terminal knot. 



Colour : Pale violet ; marginal flaps, margin of the arms and 

 terminal suctorial crisps, dark violet ; Gonads, yellow. 



Size : Breadth of Umbrella, 8 mm. Height of Umbrella, 40 mm. 



Locality ; Tropics of the Pacific Ocean, Radack Island. Chamisso. 



Genus. Leonura. 



Crambessidse without free upper arms, with ribbon-shaped, very 

 long and slender under-arms which only have suctorial crisps 

 towards the distal end above the terminal knot, mouth cross with 

 8 rays and 8 adradial suctorial crisps, which form especial frills 

 round the centre of the brachial disc. 



Species. Leonura leptura. 



Haeckel, System der Medusen. Seite, 631. 



Umbrella flat, oi'bicular, with 80 marginal flaps. In each 

 Octant 8 rectangular velar flaps, between 2 pointed triangular 

 ocular flaps. Sub-genital-ostia 3 times as broad as the pillars 

 between them. Mouth cross of the brachial disc with frills ; 

 the 8 rays in pairs. Arms very long and slender, ribbon-shaped, 

 nearly three times as long as the diameter of the Umbrella, a bundle 

 of frills, at the end which surrounds a pointed three-cornered 

 terminal knot. 



Size : Breadth of Umbrella, 100 mm. Height of Umbrella, 

 50 mm. 



Locality : South Pacific Ocean, near New Zealand. Weber. 



