186 BULLETIN OF THE 



evident that, even in deep water, there is on this west coast of Central 

 America a considerable fauna which finds its parallel in the West Indies, 

 and recalls the precretaeeous times when the Caribbean Sea was prac- 

 tically a bay of the Pacific. There are, indeed, a number of genera in 

 the deep water, and to some extent also in the shallower depths, which 

 show far greater affinity with the Pacific than with the Atlantic fauna. 

 Of course, further exploration may show that some of these genera are 

 simply genera of a wider geographical distribution ; but I think a suffi- 

 ciently large portion of the deep-sea fauna will still attest the former 

 connection of the Pacific and the Atlantic. 



I am thus far somewhat disappointed in the richness of the deep sea 

 fauna in the Panamic district. It certainly does not compare with that 

 of the West Indian or Eastern United States side. I have little doubt 

 that this comparative poverty is due to the absence of a great oceanic 

 current like the Gulf Stream, bringing with it on its surface a large 

 amount of food which serves to supply the deep-sea fauna along its. 

 course. In the regions we have explored up to this time, currents from 

 the north and from the south meet, and then are diverted to a westerly 

 direction, forming a sort of current doldrums, turning west or east or 

 south or north according to the direction of the prevailing wind. 

 The amount of food which these currents carry is small compared with 

 that drifting along the course of the Gulf Stream. I was also greatly 

 surprised at the poverty of the surface fauna. Except on one occasion, 

 when during a calm we passed through a large field of floating surface 

 material, we usually encountered very little. It is composed mainly of 

 Salpa3, Doliolum, Sagittas, and a few Siphonophores, — a striking con- 

 trast to the wealth of the surface fauna to be met with in a calm day in 

 the Gulf of Mexico near the Tortugas, or in the main current of the Gulf 

 Stream as it sweeps by the Florida Reef or the Cuban coast near Havana. 

 We also found great difficulty in trawling, owing to the considerable irreg- 

 ularities of the bottom. When trawling from north to south, we seemed 

 to cut across submarine ridges, and it was only while trawling from east 

 to west that we generally maintained a fairly uniform depth. During the 

 first cruise we made nearly fifty hauls of the trawl, and in addition sev- 

 eral stations were occupied in trawling at intermediate depths. In my 

 dredgings in the Gulf of Mexico, off the West Indies, and in the Carib- 

 bean, 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 upon such masses 



