236 BULLETIN OF THE 



number was so great as to cause the water of the harbor to appear as 

 though filled with scattered brown specks. After remaining so abundant 

 for several nights, tliey suddenly disappeared, so that we could not find 

 more than one or two in the tow-net where a hundred were seen before. 

 We also came across floating colonies of Ctenophores, of Annelid larva?, 

 and of Sagitta). These windrows of animals are no doubt largely due 

 to the complicated currents and tide eddies, the water of the open seas 

 being constrained to flow through the rather narrow passages between 

 islands. One cannot doubt that there is a plentiful supply of vegetable 

 food for the pelagic fauna of the Bahama Banks ; for the little floating 

 alga Trichodesmium is everywhere abundant. We found it present in 

 every tow we made, and indeed it was often impossible to keep marine 

 animals alive over night on account of the rapid decomposition of this 

 sea-weed scattered through the water. 



MEDUSA. 

 Hybocodon Forbesii, nov. sp. 



Plate I. Fig 1. 



A single specimen of a medusa of Hybocodon was found in Nassau Harbor, 

 March 19th. This species has been named for Mr. John M. Forbes, the owner 

 of the " Wild Duck." The bell was 2 mm. in height, its walls thin and trans- 

 parent. There were four radial tentacles ; of these only one is developed and 

 functional, the other three being rudimentary. The single tentacle which was 

 well developed was about 2 mm. long. Its proximal portion was stiiT, and pro- 

 jected almost vertically downwards from the bell margin. The distal portion 

 consisted of a bulbous swelling studded thickly with nematocysts. This swollen 

 portion was highly contractile and very sensitive. It was usually carried pro- 

 jecting inwards at right angles to the tentacle itself. The tentacle diamet- 

 rically opposite this functional tentacle was somewhat longer than the other 

 two. The entodermal cells of the manubrium were bright yellow. The 

 velum was rudimentary. 



Bougainvillia Niobe, nov sp. 



Plate I. Fig 2. 



A very interesting specimen of Bougainvillia, for which the name B. Xiobe is 

 proposed, was taken in a surface tow in Nassau Harbor, March 18th. The bell 

 was 6.75 mm. in height, and its apical portion was very thick. The tentacles 

 of the bell sprung from four bulbous swellings at the bases of the radial tubes. 

 There were between six and eight tentacles arising from each of these bunches. 



