54 EDWARD T. BROWNE. 



to alcohol, as the storage room on the ship was below freezing point. These specimens 

 have now been preserved about six years, and the tissues are still in good condition, 

 and the mesoglsea remains transparent and pliable. The jar contained at least three 

 specimens. 



Specimen A. The umbrella is about 60 mm. in diameter, and it is unbroken, 

 though the margin is torn away and the whole of the mouth. This is, however, a 

 valuable specimen, as it is the only one showing the gonads in situ, and they are in 

 good condition. 



Specimen B. This specimen is represented by one-half of the umbrella, with 

 about eight rhopalia and eight tentacles. The diameter of the umbrella is estimated 

 at about 70 mm. 



Specimen C. This one consists of only one-half of the umbrella, with seven 

 rhopalia. The diameter of the umbrella is estimated at about 75 mm. From the 

 appearance of the radial canals, Specimens B and C belong to different Medusae, and 

 not to one Medusa torn in half. In addition to the above there are four fragments 

 belonging to the margin of the umbrella, with tentacles and rhopalia. These fragments 

 may be parts of the above specimens, or of other specimens. 



Description of the Adult. The umbrella is thin and probably slightly convex in 

 shape. The margin of the mouth is studded with warts and short protuberances 

 containing nematocysts. The fragments belonging to the mouth are from the margin 

 of a large mouth with either four lips, or four short arms, about 35 mm. in length, 

 something like the oral arms of Aurelia aurita, but thinner and more membrane-like. 

 The stomach is a flat circular cavity, about two-thirds the diameter of the umbrella, 

 and its lower side is covered with a moderately thick layer of mesoglsea. 



In a normal specimen 32 radial canals should leave the stomach. Sixteen of these 

 belong to the rhopaliar series and are branched, and sixteen to the tentacular series 

 and are unbranched. All the radial canals communicate with a circular canal and also 

 with one another by means of an irregular anastomosing network of canals near the 

 periphery of the umbrella (Plate VI., fig. 3). The rhopaliar canals have opposite 

 lateral branches, which are irregular in their position on the main canal. In the 

 adult the primary lateral branches have not unfrequently lost their connection 

 with the main canal, and are in direct communication with the stomach. This is 

 evidently due to the outward growth of the periphery of the stomach cutting off the 

 proximal portion of the radial canals, including the junctions of the branches. (In 

 Aurelia aurita it is not unusual to find the interradial branched canals isolated from 

 their main canal, which then runs as a straight isolated canal from the stomach to the 

 sense organ.) The main rhopaliar canals have frequently secondary lateral branches, 

 which originate nearer the margin of the umbrella. The secondary branches were not 

 present in the ephyra stages, and were only seen in the adults. 



The gonads begin to make their appearance in the meta-ephyra stage, and are 

 then indicated by a very narrow band on the outer side of the gastric filaments. As 



