180 



THREE CRUISES OF THE '' BLAKE. 



Eminently characteristic of the Gulf Stream, and wherever its 

 influence extends, Porpitse (Fig. 86), Velellse, Physalise (Fig. 

 87), and floating barnacles (Fig. 88) have been found. In 



Fig. 86. — Porpita. ^. 



fact, these surface animals are excellent guides to the course of 

 the current of the Gulf Stream, — natural current bottles, as it 

 They are thrown up along the whole length of the 



were. 



^ During the voyage of the " Chal- 

 lenger," observations were made addi- 

 tional to those mentioned by Lyell upon 

 the transportation of seeds by fruit-pi- 

 geons ; and in the Botany of the " Chal- 

 lenger " Expedition (Chall. Ex., Bot., 

 Part III., p. 277 et seq., 1885), there is 

 an interesting Appendix on the dispersal 

 of plants by oceanic currents and birds. 



Robert Brown, Chamisso, Darwin, and the 

 French botanists attached to the "Ura- 

 nie," paid considerable attention to the 

 plants they found scattered on the shores 

 of many of the islands in the Pacific. 

 Moseley describes the masses of drift- 

 wood met with by the " Challenger " off 

 New Guinea, about seventy-five miles 

 northeast of Point d'Urville. 1 have my- 



