MAYER : MEDUSA FROM THE WESTERN ATLANTIC. 7 



OCEANIA, Pekon and Lesceur, 1809. 

 Oceania carolinas, nov. sp. 



Figs. 9-11, Plates 3, 4. 



Specific Characters. — The bell is not quite a hemisphere, and is 14 mm. in 

 diameter. The ca\nty of the bell is shallow, so that the gelatinous substance 

 is quite thick. There are 16 well-developed marginal tentacles with large, 

 hollow basal bulbs. These are only about half as long as the bell diameter, 

 but as they are usually carried coiled in a close helix they appear much shorter. 

 In addition to these well-developed tentacles there are 48 small rudimentary 

 tentacle bulbs that probably never develop into tentacles. There are 64 

 otocysts, 4 between each adjacent pair of large tentacles (see Figure 11). 

 Each otocyst contains 2 spherical otoliths. The velum is well developed. 

 There are 4 narrow, straight, radial canals. The mature proboscis (Figure 

 10) is flask-shaped, and there are 4 simple curved lips. The gonads are de- 

 veloped upon the radial tubes at about one quarter the distance from the 

 circular vessel to the proboscis. In the female the ova are very conspicuous. 

 The entoderm of the tentacle bulbs and proboscis and of the radial tubes in 

 the region of the gonads is bright yellow-green. 



This species was extremely abundant in Charleston Harbor in the early part 

 of September, 1897, and in June, 1898. 



Oceania singularis, nov. sp. 



Figs. 13, 13, Plate 4. 



Specific Characters. — The bell is 2 mm. in diameter and the sides are quite 

 straight and sloping. Near the apex of the bell there is a sharp constriction, 

 above which there is a lens-shaped apical projection. There are 16 well-de- 

 veloped marginal tentacles with large, hollow, conical-shaped basal bulbs. The 

 lashes of the tentacles are short and are covered with nematocystic cells. In 

 addition to the 16 functional tentacles there are 16 intermediate rudimentary 

 ones. There are 32 otocysts, each containing a single highly refractive spheri- 

 cal otolith. There are 4 straight radial tubes. The proboscis is quadrangular 

 in cross-section, and there are 4 simple lips. The 4 gonads are developed upon 

 the 4 radial canals near the base of the proboscis. The entoderm of the proxi- 

 mal part of each tentacle bulb is turquoise-green, and the distal part is 

 brownish-red. The entoderm of the proboscis and of the radial tubes in the 

 neighborhood 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. 



