NARCOMEDUS^E — SOLMARIS. 437 



the first two divisions are meridional and the 8-cell stage consists of 2 small cells at the animal 

 pole, 2 large cells at the vegetative pole, and 4 cells in the equatorial zone. The morula con- 

 sists of 32 cells and there is a large cell in its center which is derived from one of the large 

 vegetative cells. This large cell gives rise to a part of the entoderm of the blastula, the remain- 

 ing portion of the entoderm being derived from the superficial blastoderm as described by Maas. 

 The genital cells originate from entodermal cells of the central blastomere, which afterward 

 migrate into the ectoderm. 



Solmaris solmaris. 



Mgineta solmaris, Gegenbaur, 1856, Zeit. fiir wissen. Zool., Bd. 8, p. 265, taf. 10, fign. 4, 5, fig. lo(?). 



Solmaris gegenbauri, Haeckel, 1879, Syst. der Medusen, p. 358. 



Mgineta paupercula (young medusa ?), Gegenbaur, 1856, Zeit. fiir wissen. Zool., p. 263, taf. 10, fig. 10. 



This Mediterranean species is distinguished by the large number (6 to8)of sensory-clubson 

 each of its bell-lappets. In other respects it closely resembles Solmaris flavescens. Bell lentic- 

 ular, 25 mm. wide, 12 mm. high. 18 to 20 tentacles about as long as the bell-diameter. 

 Stomach, gonads, and tentacles milky. (See text-figure 287.) 



Solmaris corona Haeckel. 



Mgineta corona, Keferstein und Ehlers, 1861, Zoolog. Beitrag. aus Neapel und Messina, p. 94, taf. 14, fign. 7-9. 



Solmaris corona+S. coronanlha, Haeckel, 1879, Syst. der Medusen, pp. 358, 359, taf. 20, fign. 7-10. 



Solmaris corona, Browne, 1903, Bergens Museums Aarbog, No. 4, p. 30. 



( ?) Mquorea rhodoloma, Brandt, 1838, Mem. Acad. St. Petersbourg, ser. 6, tome 4, plate 2, p. 357, taf. 3, fign. 1-5. 



Browne, 1903, found this medusa off the southern coasts of Ireland and Norway. It is a 

 fairly well-known Mediterranean form. 



Haeckel attempts to separate his Solmaris " coronantha" of the Canary Islands from 

 S. corona on the ground that in S. " coronantha" there is but 1 sensory-club upon each lappet, 

 whereas he states that in S. corona there are 2 to 3 clubs upon each lappet. Browne, 1903, 

 finds, however, that there are usually 2 clubs, but occasionally only I club, on each lappet 

 of S. corona, so that Haeckel's attempt to separate the species upon so slight and evidently 

 variable character falls to the ground, and it is probable that in common with many other 

 Narcomedusae and Trachymedusae this species is widely distributed over the Mediterranean 

 and Atlantic. (See text-figures 288 and 289.) 



It bears a strikingly close resemblance to Brandt's AZquorea rhodoloma from the Pacific 

 coast of Chili, South America. 



The bell is flat-topped with a low, conical, blunt apex. Bell 14 mm. wide, 27 to 35 tentacles, 

 each 1.5 times as long as the bell-diameter. Usually 2 sensory-clubs on each lappet margin. 

 The club is mounted on a large sensory cushion which bears long bristles. This medusa is 

 distinguished from Solmaris flavescens by its large number of tentacles and its bristle-bearing 

 sensory pads, the bristles in S. flavescens being confined to the sensory-club itself. 



Solmaris forskalii. 



Polycolpa forskalii, Haeckel, 1879, Syst. der Medusen, p. 328; 1881, Report Deep Sea Medusa', Challenger Expedition, vol. 4, 

 Zool., p. 31, plate 10, figs. 1-8. — Vanhoffen, 1908, Narcomedusen Valdivia Expedition, p. 56. 



Bell flat and discoidal, 20 to 75 mm. wide. A deep circumferential furrow extends 

 around the bell, dividing the thick central part of the disk from the thin, flexible margin. This 

 margin is divided into 24 to 30 lappets which alternate with the same number of tentacles. 

 The tentacles project stiffly from the ring furrow and are all of equal length, being 1.5 to 2 

 times as long as the bell-diameter. 



There are 5 to 7 sensorv-clubs on the margin of each of the 25 lappets, one club being at the 

 outer point of the lappet and the others flanking it. Each club contains 3 to 4 crystalline ento- 

 dermal concretions and is mounted upon a sensory cushion which bears bristles. A short cili- 

 ated ridge of ectodermal cells extends upward over the exumbrella side of the lappet above the 

 club. The web-like velum spans between the lappets and forms a narrow diaphragm around 

 the edge of the bell-opening. 



