418 MEDUSAE OF THE WORLD. 



The numerous examples found by the Siboga in the Malay Archipelago have enabled 

 Maas to study the growth-stages of this medusa in detail. When the medusa is 18 mm. wide 

 the gonads are 4 large triangles on the distal ends of the 4 radial-canals, but there are only 3 

 wide centripetal canals in each quadrant. This stage is shown in my figure of a specimen from 

 Tortugas, Florida. Later, when the angles of the triangular gonads become blunted and they 

 are about to touch in the 4 interradii of the subumbrella, 4 small, new diverticula develop from 

 the ring-canal between the 3 original diverticula, thus giving 7 centripetal canals in each 

 interradial quadrant. The first of these new diverticula develop on both sides of the original, 

 large, interradial diverticulum, and then the centripetal diverticula close by the sides of the 

 radial-canals begin to develop. The medusa is most abundant from June to September, both 

 in the Malay Archipelago and at Tortugas, Florida. 



Liriope tetraphylla Gegenbaur. 

 Plate 53, fig. 4? 



Geryonia tetraphylla, Chamisso et Eysenhardt, 1821, Nova Acta Phys. Med. Acad. Leop. Carol., tome 10, p. 357, plate 27, 

 fig. 2. — Eschscholtz, 1829, Syst. der Acalephen, p. 88. 



Liriope tetraphylla, Gegenbaur, 1856, Zeit. fur wissen. Zool., Bd. 8, p. 257. — Vanhoffen, 1902, Wissen. Ergeb. deutsch. 

 Tiefsee Expedition, Dampfer Valdivia, Bd. 3, Lfg. i,p. 82, taf. 10, fig. 14.— Browne, 1904, Fauna and Geog. Maldive 

 and Laccadive Archipel., vol. 2, p. 738, plate 54, fig. 3; 1905, Report Pearl Oyster Fisheries, Gulf of Manaar, Royal 

 Soc. London, Suppl. Report No. 27, p. 152. — Maas, 1905, Craspedoten Medusen der Siboga Expedition, Monog. 10, 

 p. 61. — Bigelow, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 112. 



Xantliea tetraphylla, Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 365. 



Liriantha tetraphylla, Haeckel, 1879, Syst. c ' er Medusen, p. 286. 



This "species" is the oldest known Liriope. It appears to be quite common in the Pacific 

 and Indian Oceans. It is distinguished by its long, cylindrical peduncle with a conical base. 

 Peduncle 3 to 4 times as long as bell-radius. The gonads are upon the proximal half of the 

 subumbrella and are egg-shaped, not touching the ring-canal. The medusa appears to range 

 from about 15 to 30 mm. in width and is hemispherical, with thick, gelatinous walls. See 

 synoptic table of Liriope. L. rosacea is, I believe, only another name for this medusa, for 

 I sometimes find intergrading specimens at Tortugas, Florida (see plate 53, fig. 4), which 

 appear to have the characters of L. exigua, L. rosacea, and L. tetraphylla in varying pro- 

 portions of definiteness. I am more and more inclined to believe that all "species" with 

 triangular or heart-shaped gonads should be called L. tetraphylla, and this medusa is 

 found in all warm oceans. (See text-figure 273.) 



Liriope agaricus Vanhoffen. 



Glossocodon agaricus, Haeckel, 1879, Syst. der Medusen, p. 293. 



Liriope agaricus, Vanhoffen, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Valdivia, Bd. 3, Lfg. 1, p. 79. 



See synoptic table of species of Liriope. 



This form is distinguished by its triangular, equilateral gonads on the outer halves of the 

 subumbrella lengths of the radial-canals, touching the ring-canal. Peduncle cylindrical with 

 a conical base and is about 3 times as long as bell-radius. 7 centripetal canals in each inter- 

 radial quadrant, 3 long and 4 short. Bell about 20 mm. wide. Coast of New Zealand. This 

 is probably identical with L. tetraphylla. 



Liriope canadensis Vanhoffen. 



Glossoconus canariensis, Haeckel, 1879, Syst. der Medusen, p. 292. 



Liriope canariensis, Vanhoffen, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Valdivia, Bd. 3, Lfg. I, p. 79. 



See synoptic table of species of Liriope. 



This form is distinguished by its semicircular gonads on the proximal halt of the subum- 

 brella touching the base of the peduncle and widely separated from the ring-canal. Peduncle 

 cylindrical, with conical base, and 2 to 3 times as long as bell-radius. There are 3 centripetal 

 vessels in each quadrant, the middle (interradial) ones being longer than the adradial. The 

 mouth, gonads, stomach, and canals are rose-red. Found by Haeckel at the Canary Islands, 



in February. 



Liriope liitkenii. 



Glossocodon liitkenii, Haeckel, 1879, S )' st - ^ er Medusen, p. 293, taf. 18, fig. 5. 



Bell hemispherical, 12 mm. in diameter. There are 4 very long, slender, radially situated 

 tentacles, fully twice as long as bell-diameter. No interradial tentacles were seen in the 



