656 



MKl)l'S.E OF THK WORLD. 



flanked by 2 very small, rhopalar lappets. The lappets are so poorly developed that the bell- 

 margin is practically entire and without notches, in this respect resembling C. aeriiLa. The 

 octan<Tular arm-disk is about as wide as the bell-radius, and the 4 subgenital ostia on its 

 interradial sides are very short, narrow clefts. 



The 8 mouth-arms arise in 4 pairs from the perradial angles ot the central part of the 

 arm-disk, but separate widely, one from another, so as to project from the 8 adradial corners 

 of the sides of the disk. The 8 mouth-arms are each about as long as the bell-radius and 

 each one bifurcates near its outer end. Numerous short branches arise from the ventral 

 sides of the mouth-arms and these bear the mouths. A single long, stout filament arises from 

 each of the 4 perradial corners of the ventral side of the arm-disk at the points of bifurcation 

 of the 4 primary mouth-arm canals. In this respect the medusa differs from C. cacrulea, 

 wherein there are 4 filaments in each perradius of the arm-disk. 1 here are also more than 

 too long, slender filaments between the mouths. These filaments are longer than the bell- 

 diameter. In the closely allied C. caerulea the mouth-arm filaments are very short and incon- 

 Thc radial-muscles of the subumbrella are well-developed and form radiating, 



lamella-like ridges as in Ccxrulca. 

 There are numerous, fine, anasto- 

 mosing radial-canals and a wide 

 network of vessels near the mar- 

 gin. Color f ? ) 



Found at the Caroline and 

 Samoan Islands, tropical Pacific. 

 This description is presented to 

 show that there are no appreciable 

 differences between this medusa 

 and Forskal's Medusa cephca. 



spicuoiis. 



Fk;. 407. — "Cephea conifera," after Hacckel, in Das Syst. der Meduscn. 



Cephea cephea var. dumokuroa Agassiz 

 and Mayer. 



Cefthfa dutnokuroay Agassiz AST) Mayer, 1899, 

 Bull. Museum Comp. Zool. at Harvard 

 College, vol. 32, p. 172, plates 11, 12, 



figs- 36-39- 

 NetToitomii dumokuroay Maas, 1903, Scypho- 

 medusen der Sibogti Expedition, Monog. 

 II, p. 38. 



Bell 300 mm. wide, flat, and 

 disk-shaped with sides vertical 

 near the margin. A large promi- 

 nent domeat center ol e.xumbrella. 

 The apex of this dome is smooth and without the wart-like protuberances seen in C. cwrulea 

 and C. conifera; instead of which the protuberances of C. duniokurna are arranged in two ver- 

 ticels, confined to the sides of the dome. The upper row of protuberances consists of about 

 8 large, solid, wart-like, blunth-pointed projections, and below them is a zone of about 12 

 smaller warts not more than half as large as those of the upper row. There is a wide, shallow 

 furrow around the dome. 8 rhopalia are deeply sunken within inarginal niches. Each sense- 

 organ contains a terminal mass of white, cntodermal concretions. There is no ocellus and 

 no exumbrella sensory pit. 



The marginal lappets are so shallow that one can bareh- distinguish them, bur there are 8 

 scarcely perceptible, velar lappets in each octant, as in 6'. etrnileu and C. eoiiifera. The arm- 

 disk is about as wide as the bell-radius and there are 4 very small, round, subgenital ostia, with 

 a unitary subgenital porticus. 8 short, bifurcated mouth-arms, each about as long as bell- 

 radius; their free outer ends curve upward and the mouths are confined to the \entral sides of 

 the arms, the frilled mouths being placed upon short branches which arise from the lower side 

 ol each arm. There are neither filaments nor club-shaped appendages, and in this respect the 

 medusa differs from C. caerulea and C. conifera. The central stomach is a wide cruciform space 

 above the subgenital porticus. 32 radial-canals arise from its margin and diverge into the sub- 



