VOYAGE UP THE COAST TO PARA. 137 
tervals between, and the network of vessels on the margin is 
wonderfully fine and delicate ; the curtains hanging from the 
mouth are white and closely fringed with full flounces, some- 
what like our Aurelia. The movement is quick, the margin 
of the disk beating with short, rapid pants. Another is alto- 
gether brown and white, the seaweed-like pattern being car- 
ried down to the edge of the lobes, and the lobes them- 
selves being more delicate than those of the blue-edged one, 
the disk thinning out greatly towards the periphery. The 
brown marks are, however, darker, more distinct, and 
cover a larger space in some specimens than in others. 
This is also true of those with the blue margin, the 
brown pattern covering the whole disk in some, confined 
to a simple zone around the disk in others, and even 
entirely absent occasionally. Mr. Agassiz inclines to think, 
from the similarity of their other features, however, that, 
notwithstanding their difference of color, they all belong to 
the same species, the variety in coloration being probably 
connected with difference of sex. He has, at any rate, 
ascertained that all the wholly brown specimens caught 
to-day are males. 
We were rejoiced this morning by the sight of our own 
flag coming into harbor. We presently found that .the 
ship was the gunboat Nipsic. She had sailed from Boston 
on the 4th of July, and brought papers of a later date than 
any we have seen. The officers were kind enough to send 
us a large bundle of papers, which we have been eagerly 
devouring. 
August Sth. Another quite new and beautiful Medusa 
to-day. As we were waiting for breakfast this morning a 
number floated past, so dark in color that in the water 
they appeared almost black. Two of our party took a boat 
