VOYAGE FROM NEW YORK TO RIO DE JANEIRO. 5 
ests will help each other; when naturalists will be more 
liberal and sailors more cultivated, and natural science and 
navigation will work hand in hand. And now for my 
lecture, my first lecture on ship-board." 
The lecture was given, of course, specimen in hand, the 
various inhabitants of the branch of sea-weed giving their 
evidence in succession of their own structure and way of 
life. To these living illustrations were added drawings on 
the blackboard to show the transformations of the animals, 
their embryological history, &c.* Since the lecture, Captain 
Bradbury has fitted up a large tank as an aquarium, where 
any specimens taken during the voyage may be preserved 
and examined. Mr. Agassiz is perfectly happy, enjoying 
every hour of the voyage, as well he may, surrounded as 
he is with such considerate kindness. 
April Qth. -- Though I took notes, as usual, of the lecture 
yesterday, I had not energy enough to enter them in my 
journal. The subject was the Gulf Stream, the stream 
itself this time, not the animals it carries along with it. 
Mr. Agassiz's late observations, though deeply interesting to 
himself, inasmuch as personal confirmation of facts already 
known is always satisfactory, have nothing novel now-a- 
days ; yet the history of the facts connected with the dis- 
covery of the Gulf Stream, and their gradual development, 
is always attractive, and especially so to Americans, on ac- 
count of its direct connection with scientific investigations 
* The species of Hydroids most numerous upon the gulf-weed have not yet 
been described, and would form a valuable addition to the Natural History of 
the Acalephs. For an account of the animals of this class inhabiting the Atlan- 
tic coast of North America, and especially the New England shores, I may refer 
to the third volume of my Contributions to the Natural History of the Uni^d 
States, and to the second number of the Illustrated Catalogue of the Museum 
of Comparative Zoology at Cambridge. L. A. 
