MAYEK: MEDUSiE FROM THE TORTUGAS, FLORIDA. 61 



canals. The stomach is about two thirds as wide as the bell diameter. The 

 gonads are linear, and occupy almost the whole length of the radial canals. 

 The entoderm of the gonads, tentacle bulbs, and proboscis is blue-green. The 

 medusa is very common off the Florida Coast both in summer and winter. 



-(EQUORBA, Peron and Lesdeur, 1809. 



^quorea floridana. 



Khegmatodes floridanus, Agassiz, L., 1862, Cont. Nat. Hist. U. S., Vol. IV. p. 361. 



Specific Characters. — The bell is hemispherical and 25 mm. in diameter. 

 The gelatinous substance of the bell is thick and of a tough consistency. 

 There are 16 radial tubes and 64 well-developed marginal tentacles. The 

 tentacle bulbs are large and hollow, and are provided each with one or two 

 excretion papillsE, which project outward from the side of the bell. There are 

 about 192 otocysts, three between each successive pair of tentacles. Each 

 otocyst contains 2 spherical otoliths. The velum is well developed. The 16 

 gonads are developed upon the distal halves of the 16 radial canals. The sur- 

 face of the mature gonads is slightly convoluted. The proboscis is wide and 

 very shallow, and there are 16 slightly fimbricated lips. The gonads and the 

 edge of the bell are milky-white. Common at the Tortugas and Bahamas in 

 the spring months. 



RHACOSTOMA, Agassiz, L., 1862. 

 Rhacostoma dispar, nov. sp. 



Figs. 37-29, PI. 13. 



Specific Characters. — The bell is lens-shaped, and about 40 mm. broad and 

 20 mm. high. The cavity of the bell is remarkably small and shallow, so that 

 the gelatinous substance is very thick. The velar opening of the bell is only 

 about 5 mm. in diameter. There are about 8 very small rudimentary tentacles. 

 There are 30-40 otocysts scattered between the tentacles. Each otocyst con- 

 tains 3-5 oval-shaped otoliths (see Figure 29). There are no excretion papillje. 

 The velum is well developed. There are about 80 radial tubes, fully half of 

 which end blindly without reaching the circular tube. The gonads are situated 

 upon all of the radial tubes. They are linear, and their surfaces are slightly 

 convoluted. They do not extend quite to the peripheri of the stomach, nor do 

 they reach the circular canal. The proboscis is very wide, and may at times 

 be protruded beyond the velar opening. There are about 80 small crenulated 

 lips, which are apparently as numerous as the radial canals. The bell has a 

 faint steel-blue tinge, and the genital organs are pink. A single specimen 



