450 A. E. Verrill — Decapod Crustacea of Bermuda. 



Several species of crabs and shrimps habitually live among float- 

 ing sargassuiii, or attached to floating driftwood. This is the case 

 especially Avitli Planes minutus, Portimus Sayi, and some others. 

 That they have migrated to Bermuda in this way is very evident, 

 for they do so constantly, day by day, at the present time. 



But the majority of the species common to Bermuda and the 

 West Indies do not have such habits, and must have migrated north- 

 ward in the free-swimming larval stages. The direction of the Gulf 

 Stream and prevailing wind currents are favorable for the transpor- 

 tation of free-swimming animals from the Bahamas, Cuba, etc., to 

 the Bermudas. 



On the other hand, very few if any strictly East American species 

 have established themselves in the Bermudas, notwithstanding the 

 constant passage of vessels in (hat direction for nearly three hundred 

 years. Perhaps the temperature of the Gulf Stream is too high to 

 allow such species to be carried across it, or they may not be able to 

 endure the summer temperature of the Bermuda waters. 



There are, likewise, no Decapod species of European or Mediter- 

 ranean origin known in the Bermuda fauna, though such are known 

 to occur in other orders, especially in those groups that habitually 

 cling- to the foul bottoms of vessels. 



The chances of many species being introduced into Bermuda 

 waters by this means have been unusually good, for the great dry 

 dock has existed at the naval station for many years. And long 

 before that, even from the first settlement, the sheltered harbors and 

 beaches of Bermuda have been favorite places for the beaching of 

 vessels to clean their bottoms. 



It would be of great scientific interest, as well as evident eco- 

 nomical benefit, to experiment with the introduction of edible East 

 American and West Indian Crustacea that do not now exist at the 

 Bermudas. Among those that might succeed are the large Southern 

 Rock Crab {Menippe rnercenaria) ; the West Indian Rock Crab 

 ( Carpilius corallinus) ; the southern variety of the Edible Blue Crab 

 (Callinectes sapidus), and many others. Probably their fertilized 

 eggs could be transported far more easily than the adults, and in 

 vastlv greater numbers. With suitable arrangements at the new 

 Bermuda Biological Station, such eggs could easily be hatched and 

 the young liberated in great numbers, in suitable places. 



It would probably be useless to attempt to introduce those species 

 that are restricted to our coast north of Cape Ilatteras, such as the 

 common lobster, but there seems to be no rtason why any species 



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