AXTHOMEDL'S-E PROTIARA, HKTKROTIAHA. 



107 



canals, and a simple ring-canal. The manubrium is mounted upon a short, conical peduncle 

 and is quite wide; rectangular above, hut nearly circular in cross-section near the mouth. 

 There are 4 very small, simple lips. In Wagner's specimens the manubrium was only about 

 halt as long as the depth of the bell-cavity, whereas in Hargitt's the 

 mouth extended nearly to the level of the velar opening. This differ- 

 ence may be due to age(?) The gonads are 4 large, interradial, 

 longitudinal swellings on the sides of the stomach. The outer sur- 

 faces of the gonads are smooth. 



Wagner found a few specimens of this medusa in April, in the 

 \\ hue Sea, north coast of Russia. Hargitt found an apparently iden- 

 tical medusa in summer near No Man's Land, an island off the 

 southern coast of Massachusetts. The gonads and tentacle-bulbs in 

 Hargitt's medusa are milky in color, other parts being transparent. 

 This species is distinguished from Protiara bcroe ( = P. " trtrn- 

 iii-iiin" Haeckel) by its absence of color and lack of ocelli. 



Unfortunately no sections have been made of the manubrium. 

 Wagner's figure and description are unsatisfactory in that he leaves 

 kaiekeli," tne p os ition of the gonads in uncertainty and we can not tell whether 

 there are 4 (interradial ?) gonads or only I encircling gonad. 



FK;. 56. Protiara 



after Hargitt, in Biologi- 

 cal Bulletin. 



Protiara formosa. 



Plate 6, figs. 4, 5, and 6; plate 13, figs, l and 2. 



Halitiara fortnosa, FEWKKS, 1882, Bull. Mus. Com p. Zool. at Harvard Coll., vol. 9, p. 276, platr 4, fig. 2. -MAYK.R, 1904, Memoirs 

 Nat. Sci. Mus. Brooklyn Inst. Arts and Sci., vol. I, No. I, p. 8, plate I, fig. 8. A(IASSIZ, A., AND MAYER, 1899, Bull. Mus. 

 Comp. Zool. at Harvard Coll., vol. 32, p. 160. MAYER, 1900, Bull. Mus. Comp. Zool. at Harvard Coll., vol. 37, p. 31. 



Bell about 3 mm. high and pear-shaped with solid apical projection. There are 4 long, 

 tapering, radially situated tentacles, about two-thirds as long as the bell-height. These ten- 

 tacles are hollow, with long, tapering, basal bulbs, and their ends are usually coiled in a close 

 helix. In addition to these 4 long tentacles there are 24 to 35 short, solid tentacles, not one- 

 fourth as long as the large ones. These short tentacles are tightly coiled, their axial cells are 

 chordate and they are more like cirri than tentacles. There are no ocelli or other marginal 

 bodies. The velum is narrow. There are 4 straight, narrow radial-canals and a slender 

 circular vessel. The manubrium is pynform to conical and about halt as long as the depth 

 of the bell-cavity. The mouth is a simple, cruciform opening. The gonads are developed in 

 the ectoderm on the interradial sides of the manubrium and the ova are large and con- 

 spicuous. The entoderm of the manubrium and tentacle-bulbs in the female (plate 6, fig. 5) 

 is green, but in the males light-brown (plate 6, fig. 4). 



This medusa is very abundant at Tortugas, Florida, but is not so common in the Bahamas. 

 An apparently similar form was found by Agassiz and Mayer in the FIJI Islands, South 

 Pacific, although the Pacific form was duller in color than is usual in Atlantic specimens. 



Genus HETEROTIARA Maas, 1905. 

 Hftnotiara, MAAS, 1905, Craspedoten Medusen der Siboga Exped., Monog. to, p. 19. 



The type species is Heterotiara anonyma Maas, from the Malay Archipelago. Only two 

 imperfect specimens were found by the Siboga Expedition. 



GENERIC CHARACTERS. 



Tiarinae with 8 marginal tentacles (4 radial, 4 interradial). The ring-canal gives rise to 

 one (or more ?) blindly-ending, centripetal diverticula. Gonads ( ?) 



Heterotiara anonyma Maas. 

 Hfterotiar/2 <mon\rna, MAAS, 1905, Craspedoten Medusen der Siboga Exped., Monog. 10, p. 19, taf. 3, figs. I9~2r. 



Bell 12 to 1 6 mm. high and slightly more than half as wide. Oval, dome-like, with very 

 thick, gelatinous walls. 8 hollow marginal tentacles arise from the ring-canal and extend 

 through the gelatinous sides of the bell so as to reach the exterior at a slight distance above the 

 margin. The basal bulbs of these tentacles are small, and each one has a short, blunt, hollow. 



