LEPTOMEDUS.E — PHIALIDIUM. 



273 



derm, of stomach and tentacle-bulbs light-drab or opaque white. A specimen was found at 

 the fortugas, Florida, on June 14, 1897, and several others during the summers ot 1899 

 and 1906. 



Phialidium singularis. 



Plate 35, figs. 9, 10. 



Oceania siniularis, Mayer, 1900, Bull. Mus. Comp. Zool. at Harvard College, vol. 37, P-7. pl^4» figs- 12 > 1 3 --Nutting, , 9 OI > 

 BulhU.S. Fish Commission for 1899, vol. 19, p. 380, fig. 96.-HARr.1rr, 1904, Bull. U.S.Bureau of Fisheries, vol . 24, p. 50. 



Bell 2 mm. in diameter, sides quite straight and sloping. Near apex of bell is a sharp con- 

 striction, above which is a lens-shaped, apical projection. 16 well-developed marginal ten- 

 tacles with large, hollow, conical basal bulbs; lashes of tentacles short and covered with 

 nematocyst-cells. Besides the 16 functional tentacles, there are 16 intermediate rudimentary 

 or undeveloped ones. 32 lithocysts, each containing a single, highly refractive, spherical con- 

 cretion. 4 straight radial-tubes. Manubrium quadrangular in cross-section, 4 simple lips. 

 The 4 gonads are developed upon the 4 radial-canals near base of stomach. 



The entoderm of the proximal part of each tentacle-bulb is turquoise-green; the distal 

 part is brownish-red. The entoderm of the stomach and of the radial tubes in the neighbor- 

 hood of the gonads is of a delicate turquoise tinge. 



A single specimen of this medusa was found in Newport Harbor, Rhode Island, on 



August 22, 1896. 



This medusa appears to be distinguished by the remarkable lens-shaped, gelatinous cap 

 upon apex of bell, and by the fact that the gonads are almost adjacent to the sides of the 

 manubrium. Unfortunately only a single specimen has been observed. 



Phialidium pacificum Maas. 



Oceania pacifica, Agassiz, A., and Mayer, 1899, Bull. Mus. Comp. Zool. at Harvard College, vol. 32, p. 167, plate 5, fig. 17. 

 (??) Phialidium pacificum, Maas, 1906, Revue Suisse de Zool., tome 14, p. 91, plate 2, fig. 7. 



CHARACTERS OF THE FIJIAN SPECIMENS. 



Bell moderately thick, but very flexible, hemispherical, 6 mm. in diameter. 16 thin, 

 flexible tentacles of moderate length. Tentacle-bulbs large. There are 2 lithocysts between 

 each successive pair of tentacles, and each lithocyst contains a single spherical concretion. 

 Velum well-developed. There are 4 straight, narrow radial-canals, in middle regions of 

 which the small, immature gonads are developed. Manubrium short, 8 simple lips. The 

 entoderm of the tentacle-bulbs, of the stomach, and of radial-tubes in the region of the gonads 

 is emerald green. Several specimens found at Suva and at Nukulau Islands, Fiji Islands, 

 South Pacific, in December, 1897. 



Maas found a single specimen of a medusa at Amboina, Malay Archipelago, which bears 

 some resemblance to the Fijian specimens, but it has only 4 lips, while the medusae from Fiji 

 have 8. Moreover, the medusa from Amboina was smaller than those from Fiji, but had well- 

 developed gonads, whereas the gonads of the Fijian medusae were only beginning to appear. 



The Malayan medusa is described by Maas as follows: Bell about 5 mm. in diameter, 

 32 equally spaced tentacles of a size similar each to each, and all somewhat less than halt as 

 long as bell-radius. There are o to 2 lithocysts between each successive pair of tentacles. The 

 4 large oval gonads occupy the middle thirds of the 4 radial-canals. This medusa may be 

 identical with P. discoidum. 



Phialidium iridescens Maas. 

 Phialidium iridescens, Maas, 1906, Expedition Antarctique, S. Y. Belgica, Medusen, p. 12, taf. 1, fig. 6. 



Bell 4 to 5 mm. wide, with about 32 tentacles, of which about 16 are well developed, with 

 wide, conical bases, and 16 are small. No cirri. Stomach wide, with 4 small lips having 

 complexly folded margins. 4 spindle-shaped gonads at middle points of the 4 radial-canals. 

 Subumbrella iridescent. Antarctic Ocean, about 70 to 71 S. lat., 82 to 93 W. long. 



