MAYER ; MEDUSiE FROM THE TORTUGAS, FLORIDA. 31 



HALITIARA, Fewkes, 1882. 



Halitiaxa formosa, Fewkes. 



Halitiara formosa, Fewkes, J. W., 1882, Bull. Mus. Comp. ZoiJl. at Harvard Coll., 

 Vol. IX. p. 276, PI. IV. Fig. 2. 



Specific Characters. — The bell is 3 mm. in height, and is provided with a 

 solid apical projection. There are four long, radially situated tentacles, the 

 distal ends of which are usually carried coiled in a tight helix. These tentacles 

 are hollow, and have well-developed basal bulbs. In addition to these there 

 are 24-35 short, solid tentacles that are usually carried tightly coiled. The 

 velum is well developed. There are 4 straight, narrow radial tubes and a 

 narrow, simple, circular vessel. The proboscis is pyriform, and extends for 

 about half the distance from the apex of the bell ca\'ity to the velar opening. 

 The mouth is a simple round opening, and there are no prominent lips. The 

 gonads are situated within the proboscis. In the case of the female the ova 

 are very large and conspicuous. The entoderm of the proboscis and tentacle 

 bulbs in the females is green ; in the males, light brown. This medusa is cer- 

 tainly the commonest of all at the Tortugas, Florida, during the summer 

 months. We have found this species in the Fiji Islands. 



BCTOPLEURA, Agassiz, L., 1862. 

 Ectopleura minerva, nov. sp. 



Fig. 38, Plate 16 ; and Fig. 135, Plate 37. 



Ectopleura, sp , Fewkes, J. W., 1883, Bull. Mus. Comp. Zool. at Harvard CoIL, 

 Vol. XI. p. 85, PI. I. Fig. 11. 



This form possesses but two marginal tentacles instead of four, as in all other 

 species of Ectopleura. 



Specific Characters. — The bell is 2.5 mm. in height and is pear-shaped, hav- 

 ing a well-developed apical projection. The gelatinous substance is of only 

 moderate thickness. 8 rows of nematocyst cells extend from the tentacle bulbs 

 to the bell apex. There are 2 well-developed tentacles, and 2 small tentacle 

 bulbs. There are 6-9 separate, wart-like swellings upon the upper (aboral) 

 side of each tentacle. These swellings are crowded with nettling cells. The 

 velum is well developed. There are 4 straight, narrow, radial canals and a 

 slender circular vessel. The proboscis is pear-shaped and is about | as long as 

 the height of the bell cavity. A simple, short style-canal extends upward into 

 the apical projection of the bell. The entoderm of the proboscis and tenta- 

 cles is of a delicate purple, while the supporting lamella of the bell is of a 



