to Prof. E. Forbes. 23 



dredge moving. No sieves had been furnished by the dock-yard, 

 nor, although I ransacked the Rua d' Ouvidor from one end to 

 the other, could I obtain the requisite materials for making one. 

 In this dilemma I procured a wire-gauze dish-cover and a ma- 

 chine for washing rice in, both of which Huxley and myself found 

 to answer capitally. We dredged in Three Fathom and Botafogo 

 bays in from three to five fathoms, sand. Among the results are 

 a fine ScuteUa with notched and perforated margins [R. 155 to 

 159], a boring Modiola [R. 102] *, three species of Dentalium 

 [R. 1^ t, and otliers of the genera Nucula, Oliva, Ancillaria, Su- 

 bula, Fusus, &c., in all about forty-five species of mollusca J. But 

 the most interesting acquisition was a fish of that most anomalous 

 genus Amphioxus. "^It appears to difi'er from the European spe- 

 cies in the relative position of the anus, the only distinction I 

 can observe, judging from brief descriptions. Besides the spe- 

 cimens in my general collection, I inclose some in a small bottle 

 which I beg you will transmit to our friend Prof. Goodsir, who 

 has so admirably described the structure of this singular fish. 

 Huxley, with his usual industry and success, has been working 

 away at it, and pointed out to me distinct hepatic and generative 

 systems, neither of which Goodsir mentions. The spermatozoa 

 were quite distinct. We found the Amphioxus in from five to 

 two fathoms in sand of various degrees of coarseness ; it has ex- 

 actly the habits of the Ammoccetes in Britain, burying itself in 

 the sand and moving through it with extraordinary rapidity. 



A visit to the market at Rio wdll repay the collector. He 

 ■ought to go early in the forenoon when the fishing-boats come 

 in and are drawn up on the muddy shore. These are long canoes 

 hollowed out of the trunk of a tree managed by one or two men. 

 The variety of fish is considerable and constantly varies. The 

 most plentiful kinds were a small Clupea [S. 15], and an En- 

 graulis [S. 18] with a broad lateral silvery band. Here and there 

 are large baskets filled with loathsome land-crabs covered with 

 black slimy mud, along with others containing large and hand- 

 some LupecB [C. 50 and 51], and a fine Palemon [S. ] . iVmong 

 the articles exposed for sale I was surprised to see small sharks 

 of various kinds, and cuttle-fish {Octopus) [S. 36], and Loligo 

 [S. 2]. 



In St. Salvador, the capital of an extensive empire, a city con- 

 taining 250,000 inhabitants, there is little for a stranger from 

 Europe to admire. On landing he is apt to turn up his nose at 

 the stench and filth which he encounters under a tropical sun, 



* M. cubitus, Say. 



t One of these is the tube of an Annelid. — E. F. 



X Among the molhisca were Oliva micans, Solen Sloanei, a new Luci- 

 nopsin, and a new XucuIq and some other new shells. 



