8 THE DEPTH AND MAEINE DEPOSITS OF THE PACIFIC OCEAN. 



formation to the patches discovered off the east coast of the United States 

 by the earlier dredgings of the Coast Survey, of Pourtales, and of the 

 'Blake.' . . . 



" Nearly everywhere along our second line of exploration, except on the 

 face of the Galapagos slope, we trawled upon a bottom either muddy or 

 composed of Globigerina ooze, more or less contaminated with terrigenous 

 deposits, and frequently covered with a great amount of decayed vegetable 

 matter. We scarcely made a single haul of the trawl Which did not bring 

 up a considerable amount of decayed vegetable matter, and frequently logs, 

 branches, twigs, seeds, leaves, fruits, much as during our first cruise. 



" I was struck, while trawling on our second line between the Galapagos 

 and Acapulco, to observe the great distance from shore to which true terrig- 

 enous deposits were carried. There was not a station there occupied of 

 which the bottom could be characterized as strictly oceanic. At our most 

 distant points from shore, the bottom specimens invariably showed some 

 trace of admixture of terrigenous material. A very fine mud was the char- 

 acteristic bottom we brought up, often very sticky, and enough of it usually 

 remained in the trawl, even when coming up from depths of over 2,000 

 fathoms, materially to interfere with the assorting of the specimens con- 

 tained in our hauls. This mud continued all the way from the Galapagos 

 to Acapulco, and up to the mouth of the Gulf of California, where it became 

 still more of an impediment to dredging, so that little work was done until 

 we passed the Tres Marias. Even then the trawl was ordinarily well filled 

 with mud, and with it came up the usual supply of logs, branches, twigs, and 

 decayed vegetable matter. 



" On going farther north, into the Gulf of California, the nature of the 

 bottom did not change materially from what it had been along the coast 

 from Acapulco to Cape Corrientes ; it was the same viscid mud, mixed occa- 

 sionally with Globigerinffi and masses of vegetable matter. So we found 

 the trawling most difficult from the weight of the mud brought up, but 

 occasionally a haul was made which more than repaid us for the time spent 

 on the less productive ones. 



" In the dredgings of the ' Blake ' in the Gulf of Mexico, off the West 

 Indies, and in the Caribbean, my attention had already been called to the 

 immense amount of vegetable matter dredged up from a depth of over 

 1,500 fathoms on the lee side of the West India Islands. But in none of 

 the dredgings we made on the Atlantic side of the Isthmus did we come 



