48 PLANTS, SEEDS, AND CURRENTS 



summed up in Vol. CVIII. (1889) ; but fifty-six floats were afterwards 

 returned, and this led to a final summary and tabulation of results 

 in Vol. CXIV. (1892). This final report is said to have been accom- 

 panied by a chart in which the Prince of Monaco laid down the 

 tracks of all of the recovered floats. This chart, to my great dis- 

 appointment, I failed to find. Reference to these very important 

 investigations has been made in various English journals, such as 

 Nature and the publications of the Royal Geographical Society. 

 The Prince himself contributed a general account of his results to 

 the Proceedings of the Society just named for 1892 in a paper 

 entitled " A New Chart of the Currents of the North Atlantic." 

 He read a paper before the British Association in 1892, but it is not 

 given in the Annual Report. His results will be utilised, as occasion 

 requires, in the succeeding pages ; but it may be here observed that 

 these floats were stranded on all the eastern shores of the North 

 Atlantic from the North Cape to Morocco. About 9 per cent, of the 

 recoveries were returned from the Canary Islands and about 10 J per 

 cent, from the West Indies and Central America. The reader will 

 perhaps be surprised at the large number of these floats that reached 

 the tropical regions of the New World, and this will prepare him for 

 much that follows in the succeeding pages of this chapter. 



The Value of Bottle-drift Data for the Study of the 

 Dispersal of Seeds by Currents. — I will not enter here into the 

 old controversy as to the value of bottle-drifts for the investigation 

 of currents. Here, as in most other controversial matters, the via 

 media between wholesale condemnation and uncritical acceptation 

 may be confidently pursued. We are only now concerned with the 

 surface-flow, which is all that the currents signify for us in the 

 transport of floating materials. Although, as the compiler of the 

 American charts remarks, the individual drifts are but the resultant 

 effect of all the forces to which the bottle is exposed during its 

 passage, yet, as he goes on to say, the tracks followed by these float- 

 ing bottles furnish a fair conception of the drift- currents. When 

 we look at the American and German charts and notice how uniform 

 and consistent is the direction taken by bottles cast into the sea 

 within the limits of well-known currents like the Gulf Stream and the 

 Main Equatorial Current, it would be idle to cavil at the assumption 

 that they are transported by these currents. The water-logged 

 derelict from off Cape Hatteras, the baulk of mahogany from West 

 Indian waters, the living turtle from the warm latitudes of the New 

 World, the floating bottle containing the record of its start in Cuban 

 waters or in Florida seas, the buoyant seed that could only have 

 grown in the West Indian islands or on the tropical mainland of 

 America, all tell the same story when they reach the coasts of 

 Europe. 



The Proportion of Recoveries. — Naturally, the proportion of 

 recoveries among ordinary bottles is small; but much depends on 

 locality. Dr. Schott especially alludes to this matter (p. 3, etc.). 

 The proportion may be as high as 10 per cent, in the case of bottles 

 dropped overboard in the warm latitudes of the middle of the 

 Atlantic, whence they are borne westward to the West Indies; and 



