370 



SCIENCE. 



[X. S. VoL.XVIII. No. 455. 



island. In common with most of the Bahama 

 banks these shallow flats are veritable sub- 

 marine deserts. Here and there one finds a 

 small cluster of coral heads and gorgonians, 

 but almost everywhere the bottom is a flat 

 barren waste of sand supporting a sparse 

 growth of coralline algse. Not only is the 

 bottom deficient in living forms, but the 

 pelagic life in the water over these flats is 

 poor to an even more marked degree both 

 in number and variety of forms. This 

 water is more or less charged with a floc- 

 culent mass of finely divided mud similar 

 to that commonly met with off the main- 

 land coast of Florida, and evidently churned 

 up by the currents caused by winds and tides. 

 This floating material clings readily to pelagic 

 animals and plants and appears to be rapidly 

 fatal to the majority of pelagic creatures. 

 Among medusae only a few species allied to 

 Gonionenius appear to thrive in this water of 

 the Bahama banlis. 



Almost no Sagittse or Salpse and remarkably 

 few Crustacea or Medusse are found in the 

 water of the shallow banks, whereas these 

 forms are abundant over the Tongue of the 

 Ocean where the depth varies from 500 to 

 1,000 fathoms, and to the northward of New 

 Providence Island in water 1,500 to 2,000 

 fathoms deep. Indeed, whenever the wind 

 becomes reversed and conies from a westerly 

 direction the pelagic hauls in Nassau harbor 

 become rich in truly oceanic forms which 

 have evidently drifted in from the Tongue of 

 the Ocean. 



An idea of the relative poverty of the 

 pelagic fauna of the Bahamas as compared 

 with that of the Tortugas will become ap- 

 parent from the fact that the most assiduous 

 efforts in surface hauls at the Bahamas brought 

 to light only 43 speeiea of medusae, while 90 

 species were found by the writer at the 

 Tortugas. The writer once drew a large sur- 

 face net for three miles through the most 

 promising looking ' slick ' over the bank with- 

 out capturing a single marine animal. 



The coral reefs of the Bahamas are richer 

 than those of the Tortugas where the corals 

 were largely killed twenty-four years ago by 



a sudden influx of ' poisoned ' water apparently 

 from the mainland of Florida. 



A wonderful reef, rich especially in 

 Madrepora, Agaricia, Dendrogyra and Gorgon- 

 ians stretches along almost the entire eastern 

 shore of Andros Island. At New Providence 

 Island also one finds a remarkable reef abound- 

 ing in Porites, Mwandrina, Madrepora palmata 

 and Gorgonians off Clifton Point, while an- 

 other cluster especially rich in Mceandrina and 

 Orbicella lies off the eastern point of New 

 Providence. There are also good reefs within 

 Nassau harbor, and, indeed, the expedition 

 met with remarkable success in its collection 

 of corals, obtaining some of the largest and 

 most perfect stocks ever taken from the West 

 Indian region. 



In comparison with that of the Tortugas 

 reefs the fish fauna of the Bahamas is mark- 

 edly poor. It is evident also that the inverte- 

 brates are not so abundant among the 

 Bahamas corals as they are among those of 

 the Tortugas. This, however, does not ap- 

 ply to the Actinians, which are more numer- 

 ous in both number and variety than at the 

 Tortugas. 



The Bahama region is richer in corals, 

 poorer in fishes and invertebrates, and far 

 poorer in pelagic life than that of the 

 Tortugas. Indeed, as Bigelow aptly states, 

 the Bahamas lie upon the wrong side of the 

 Gulf Stream. In this respect the situation 

 of the Tortugas is almost ideal, for they are 

 surrounded by the purest of ocean water, and 

 the prevailing winds, both in summer and 

 winter, drift upon their shores the rich pelagic 

 life of the Gulf Stream. 



It is true that the Tortugas afford prac- 

 tically no opportunity for the study of land 

 fauna or flora, but there is no place known to 

 the writer in the American Tropics where 

 both land and marine faunae are exceptionally 

 rich. For the study of marine life we must 

 seek the borders of the Giilf Stream. 



In considering the question of the establish- 

 ment of a laboratory for research in marine 

 zoology we must, I thinli, confine ourselves 

 to the problem of the study of the ocean and 

 leave that of the study of the land fauna to 



