354 MEDUS.E OF THE WORLD. 



Olindias sambaquiensis F. M tiller. 



Olindias sambaquiensis, Muller, 1861, Archiv. fiir Naturges., Jahrg. 27, p. 312, taf. 9. — Haeckel, 1879, Syst. der Medusen, 



p. 254. 

 Olindias sambaquensis, Maas, 1905, Craspedoten Medusen der Siboga Expedition, Monog. 10, p. 48. — Bigelow, H. B., 1909, 



Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 109. 



Bell 50 to 100 mm. wide and 20 to 30 mm. high. 80 to 100 stiff, hollow tentacles arising 

 from sides of bell, slightly above margin; these are not quite as long as bell-radius and arise 

 in the radii of the radial and centripetal canals. There are also 200 to 300 very flexible, long, 

 hollow tentacles which arise from the bell-margin and are 3 to 6 times longer than bell-diameter. 

 100 to 200 club-shaped, marginal projections, some of which develop into flexible tentacles. 

 160 to 200 paired lithocysts at bases of the stiff tentacles. Velum well developed. Stomach is 

 4-sided, narrow, and prismatic, almost as long as bell-radius. 4 simple lips. 4 complete radial- 

 canals, and as many as 108 blindly ending, centripetal canals, 27 in each quadrant. The 

 gonads cover nearly the entire lengths of the 4 radial-canals. Each gonad is swollen and 

 linear and has 20 to 40 tree-like, branching processes over its surface when mature. 



Color bright and variable with mingled yellow, greenish-yellow, red, brown, and black; 

 canal-system red. 



This species is found near shore off the west coast of the Island of Santa Catharina at 

 Sambaqui, off the coast of Brazil, and is abundant upon the surface during calm days in 

 winter. It is distinguished from 0. tenuis mainly by its greater number of blindly ending, 

 centripetal canals. There are as many as 27 such canals in each quadrant in large medusae 

 of O. sambaquiensis, while there are only 7 to 10 in 0. tenuis. These centripetal vessels increase 

 in number as the medusa grows in size. 



The best description is that of F. Muller, the only naturalist who has seen the medusa. 



O. tenuis is probably only a small, northern variety of 0. sambaquiensis. 



Olindias tenuis Browne. 



Plate 47, figs. 8 to 10; plate 48, figs. 1 to 7. 



Halicalxx tenuis, Fewkes, 1882, Bull. Mus. Comp. Zool. at Harvard College, vol. 9, p. 277, plate 7, fig. 15.— Mayer, 1900, 

 Bull. Mus. Comp. Zool. at Harvard College, vol. 37, p. 63, plates 5, 6, figs. 12, 13.— Goto, 1903, Mark Anniversary 

 Volume, p. 15. 



Olindias tenuis, Browne, 1904, Fauna and Geog. Maldive and I.accadive Archipelagoes, vol. 2, p. 737.— Mayer, 1904, Mem. 

 Nat. Sci. Brooklyn Inst. Museum, vol. 1, p. 23, plates 5, 6, figs. 50-59.— Bigelow, H. B., 1909, Mem. Mus. Comp. 

 Zool. at Harvard College, vol. 37, p. 109. 



Mature medusa. — Bell hemispherical, 35 mm. in diameter. Gelatinous substance quite 

 rigid. About 90 to 150 tentacles. 32 to 54 of these are straight, about one-third as long as 

 the bell-diameter, and arise from the sides of the bell in a zone at a short distance above the 

 margin. These tentacles are besprinkled with wart-like clusters of nematocysts and near 

 their outer ends, on the aboral side, one finds an elongate, pad-like cluster of nematocyst- 

 cells (plate 48, fig. 4), having a sucker-like appearance, which actually functions as a powerful 

 organ of adhesion, enabling the medusa to anchor itself to stones, seaweed, etc. Besides the 

 short, straight tentacles there are about 40 to 60 others, very flexible and often coiled in 

 close helices; when extended, these tentacles are about 4 times as long as bell-diameter; they 

 arise from the bell-margin, below the zone of projection of the straight tentacles. A power- 

 ful strand of longitudinal muscle fibers extends throughout the entire length of the inner 

 (velar) side of each of these marginal tentacles, while half-rings of nematocysts are found at 

 regular intervals upon their outer sides (plate 48, figs. 5 and 6). 



The tentacles are thus comparable in their structure to the long ones of Physalia. They 

 terminate in a knob-like cluster of nematocysts and upon their inner (axial) sides, near the 

 distal end, there is a flat, pad-like cluster composed of very elongate and thickly crowded 

 ectodermal cells which occasionally serves as a weak organ of adhesion. In addition to the 

 tentacles there are about 64 to 69 bluntly rounded papillae upon the bell-margin, between the 

 tentacles. There are 64 to 108 lithocysts on the inner side of, and above, the ring-canal, a pair 

 on either side of the origin of each and every one of the short, straight tentacles. Each 

 lithocyst contains a single spherical concretion. There are 4 straight, narrow radial-canals 

 and 28 to 40 diverticula, which extend inward from the circular vessel and end blindly in the 



