= ae Be BS Fie 
sia 
his Voyage to South America. — 445 
has pointed out to me that in the narrative of the voyage of 
the Nassau fleet, undertaken in 1623, as given in Binney’s 
Voyages, vol. iii. p.9), it is recorded that on the 19th and 
20th of January, 1624, when the fleet was off the coast of 
South America in lat. 42° 15'S., “the sea near them was in 
- many parts discoloured with an infinite number of small red 
shrimps.” On our return to the Strait, we continued our 
operations till the middle of June, when the increasing seve- 
rity of the weather caused us to move northwards for winter- 
quarters. We reached Rio de Janeiro on the 1st of July, and 
remained there for three months and a half. I need not des- 
cant on the glorious scenery or the wonderful profusion of 
animal- and plant-life in that magnificent country; for that, I 
presume, is well known to you. I could not afford time for 
any very long journeys, but went far enough to see the 
virgin forests in all their glory. I paid two visits to the house 
of a most hospitable Scotchman who lives on the Serra do 
Mar, about fifty miles from Rio; and I spent a few days at 
Tijuca, about ten miles from the city, where I saw the most 
wonderful exhibition of boulders that it has ever been my 
lot to witness. 
The mention of Tijuca reminds me of a matter that I 
shall feel much obliged to you if you can give me a 
little information upon, viz. how far is the development 
of the land and freshwater decapods made out? am. 
‘aware that the crayfish is stated not to undergo any meta- 
morphosis in the young state; but Ihave not been able to 
ascertain, in the limited number of books which I have here 
for consultation, whether the same thing holds good in the 
Brachyurous Decapoda. I obtained several specimens of a 
crab, in the province of Rio de Janeiro, which frequents 
streams and damp rocks in their vicinity; and while exploring 
the banks of a cascade in the neighbourhood of Tijuca, I ob- 
tained a female specimen, which, to my surprise, had between 
fifty and sixty fully developed live young ones under the 
pleon, in the ordinary position of the ova. These little crea- 
_ tures were very active, and several escaped on the parent 
being captured; but I have preserved a number of them, and 
= _Isend you specimens in this letter, together with -a careful 
sketch of the parent. ‘This occurrence, it appears to me, goes 
far to prove that this species either undergoes no marked 
metamorphosis between the egg and the perfect animal, or 
else that the metamorphosis takes place while the young ani- 
mal is beneath the pleon of its parent. The body of the adult 
crab is of a dull purple colour; the legs are of a considerably 
paler tint. [App., VII.; Pl. XXI. fig. 3.] : 
