Introduction v 



The Gulf, 700 miles in length by 100 in average width, has an abun- 

 dant and varied fish fauna. Its fishery resources, although great, remain 

 undeveloped except for the important pearl-shell industry, in connection 

 with which an original method of pearl-oyster cultivation is practiced. 

 A dozen species of subtropical food fishes of Atlantic origin are found 

 here unchanged; whales are common and porpoises abound. Sword- 

 fish, sailfish and tuna have been taken in considerable numbers by the 

 sportsmen. An account of the fishery resources of the region will be found 

 in the first paper, pages 433 to 452. The mouth of the Gulf is nearly 300 

 miles in width between Cape San Lucas and Cape Corrientes. 



With a salubrious climate, good harbors, and known to civilization 

 since the time of Cortez, it has but a sparse population about its shores, 

 and that largely, at the southern part. The Gulf remains practically an 

 unsailed sea for the sole reason that its northern end does not touch 

 United States territory. It should be a highway of ocean traffic to the 

 west coast of tropical America. 



Large zoological and botanical collections were made by the ' Alba- 

 tross' Expedition of 1911, along both coasts of the Peninsula and on 

 islands in the" Gulf, while oceanographic work was carried on daily during 

 the voyage of more than a thousand miles from Cape San Lucas to Mon- 

 terey, California. The hauls of the dredge along 'this course yielded 

 hundreds of deep-sea fishes and thousands of invertebrates from depths 

 varying from 284 to 1760 fathoms. Seven of these were in depths greater 

 than one mile, one being in a depth of two miles. The large collection of 

 deep-sea fishes brought back by the expedition contains 49 species, that 

 of shore fishes 185 species. The collection of echinoderms numbered 

 2343 specimens of 117 species, and of brachyuran crabs 56 species. All 

 of these collections were productive of species hitherto unknown. 



The very large collection of mollusks from deep water and along 

 shore contains so many new and previously known forms that it is being 

 reported upon at great length by Dr. Paul Bartsch. The work will be 

 published in separate volumes abundantly illustrated, volume one being 

 practically completed both as to text and illustrations. The studies 

 already made show that there is a close affinity with the molluscan fauna 

 of the Panamic region. Members of widely distributed groups are com- 

 mon to both areas, while those less widely distributed show marked 

 diversion from those of the Panamic faunal area, and less close relation- 

 ship with those of the California faunal area extending from the end of 

 the Peninsula northward to Santa Barbara, California. It is found that 

 the mollusks dredged in Magdalena Bay are related to those of the Gulf 



