OBSERVATIONS ON PLANT PLANKTON. 38? 



half way between them. Its only other known habitat is in the 

 island of S. Mary, one of the Azores, whence it was sent by the late 

 Mr. T. C. Hunt. Through (as I suppose) quoting from memory, 

 Watson has recorded this plant in Godman's The Azores under the 

 name of " Pediosia macrantha Lowe '? " ; adding, " Whether this be 

 the macrantha or arcjentea of Lowe, I cannot absolutely determine, 

 though the long and decidedly stalked legumes seem to place the 

 Azore specimens under the former name." But a reference to the 

 Flora of Madeira shows that the stalked legumes are characteristic 

 of P. arfjentea, i.e. Lotus arriyrodes, not of L. macrantlms. And my 

 own specimen from the Azores (T. C. Hunt, 1848) agrees perfectly 

 with Madeira L. argyrodes, and not at all with L. macranthus, whicli 

 should therefore be erased from the Azores Flora. 



OBSERVATIONS ON PLANT PLANKTON.* 

 By George Murray, F.R.S. 



At the request of the Board I have carried out a series of 

 observations on the minute free-floating vegetation, especially of 

 the west coast. The importance of a study of such organisms, as 

 the basis of nutrition of all life in the sea, has long been recognised, 

 but very little has hitherto been done in the way of investigation. 

 The main observations were made [in 1896] on board the ' Garland' 

 in three series, viz. the first from 26th March to 6th April ; the 

 second from 28th July to 15th August; and the third from 2nd 

 December to 8th December. In March to April, the observations 

 were made in the North Sea, and on the west coast of Loch Linnhe, 

 the Sound of Jura, and principally in the Clyde sea-area. In July 

 to August a week was spent in visiting the former stations and 

 others in the Clyde sea-area, and the remainmg time in the Sound 

 of Islay, Sound of Jura, Firth of Lorn, Loch Etive, Loch Linnhe, 

 Loch Aber, Sound of Mull, the sea round Rum, Eigg, and 

 Ardnamurchau, Locii Nevis, Loch Houru, Raasay Sound, &c. In 

 December, observations were made in Loch Aber, Loch Linnhe, 

 Firth of Lorn, and the Clyde sea-area. The material obtained at 

 these times was all preserved, and its working out in detail occupied 

 me for a considerable period in London. 



Methods. — In addition to tow-netting with fine silk nets — the 

 method of capture usually employed — I have made use of a cylin- 

 drical silk bag, about H feet long and 3 or 4 inches wide. This 

 was tied to the nozzle of the hose, there being a lateral overflow 

 vent near the top of the bag ; and, on pumping through it with the 

 donkey engine from an intake pipe 8 feet below the surface, good 

 results were obtained. This method, first employed by Dr. John 

 Murray, enables one to work when steaming, and is often convenient 

 in weatlier that is too rough for tow-netting. The fixing and 



* Beprinted from the Fifteenth Annual Report of the Fishery Board of 

 Scutluiul, part iii. pp. 212-218. 



2 c 2 



