264 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



evidently in a state of development. Four simple oral 

 tentacles with clusters of nematocysts. 



A specimen taken at Port Erin, April 18th, 1894. 

 Umbrella about 3 mm. in diameter. Sixteen large ten- 

 tacles and six small ones. The oral tentacles are once 

 dichotomously divided, each branch terminating in a 

 cluster of nematocysts. It has been observed in several 

 species of medusae which have branched oral tentacles in 

 the adult stages that they start life with simple, unbranched 

 tentacles. In Margelis the number of branches increases 

 with age. 



Two specimens taken at Port Erin, June 5th, 1893, 

 about 2 mm. in diameter. Sixteen large tentacles, with 

 reddish brown tentacle bulbs, and ten small tentacles, 

 with faintly coloured brownish tentacle-bulbs. Four oral 

 tentacles, once dichotomously divided, with terminal 

 clusters of nematocysts. 



A specimen taken at Plymouth, September 25th, 1893. 

 Umbrella about 1 mm. in diameter. Sixteen large 

 tentacles with dark brown tentacle-bulbs, and ten small 

 tentacles. Four unbranched oral tentacles. 



Three specimens taken at Port Erin, April 27th, 1894. 

 Umbrella about 4 mm. in diameter, with 25, 28, and 

 30 uniform tentacles. Tentacle-bulbs dark red and very 

 conspicuous. Four oral tentacles once dichotomously 

 divided. Other specimens taken on May 5th and 9th 

 somewhat similar to the above. 



The youngest medusa of this series starts with sixteen 

 tentacles and a small bulb. The other specimens show a 

 gradual increase of 20, 22, 25, 26, 28 and 30 tentacles, the 

 maximum number is probably 32. The young tentacles 

 at first have colourless bulbs, but colour appears as they 

 increase in size. In some of the largest specimens all 

 the tentacles are alike in colour and size. . The oral 



