DEPARTMENT OF MARINE BIOLOGY. I5I 



surprisingly rapid, and that the free-swimming stage of the planula may last 

 long enough for corals to be drifted fully 800 miles by the Gulf Stream. 

 He finds, also, that the peculiar and very characteristic associations of definite 

 species of corals is determined by local conditions, such as the presence or 

 absence of currents, roughness or calm of the water, etc. Certain species can 

 grow only in rough, others only in protected waters, others must have strong 

 currents, and still others weak currents for their development. 



Prof. John B. Watson made an elaborate study of the nesting habits of the 

 noddy (Anous stolidus) and the sooty terns (Sterna fuliginosa) , which nest 

 upon Bird Key, Tortugas, from May to August. It will be impossible to do 

 justice in a brief review to his painstaking and interesting work, representing 

 as it does the results of the most thorough and suggestive study of the life- 

 processes in sea-gulls yet attempted. He reared the young birds and found 

 that they could learn their way through a maze to their food. The adults 

 could also learn to overcome obstacles in seeking to sit upon the egg. The 

 noddy builds its nest in bushes, and while so doing is quite shy, but if an egg 

 be placed in the nest it loses all shyness and sits upon the tgg as if it were its 

 own. Both male and female build the nest, but the male alone procures food 

 for both during this period, the female constantly guarding the nest. After 

 the egg is laid both male and female fly away to fish and take their turns in 

 brooding the egg at intervals of about 2 hours. The egg hatches after 32 to 

 35 days of incubation. The noddy does not recognize its own egg, but will 

 readily incubate the egg of the sooty or any object, colored or uncolored, 

 bearing more or less resemblance to an egg. It recognizes the locality of its 

 nest and returns to the old locality if the nest be moved, but it will accept an 

 artificial nest placed in the old nest locality without hesitation. Dyeing one 

 of the mates in strange colors caused the undyed bird to attack it, and indeed 

 all other birds upon the island displayed excitement at the appearance of a 

 dyed bird. 



The sooty tern nests upon the ground and recognizes the exact locality 

 of its nest; if, however, the nest be raised vertically, the bird readily 

 alights upon it; then if after an interval it be lowered the bird attempts to 

 alight in the air above the nest in the place where the nest was formerly. A 

 slight horizontal movement of the nest causes great confusion in the bird. 



Professor Watson caused adult birds to be taken from Bird Key to Havana, 

 80 miles, to Key West, 66 miles, and to Cape Hatteras, 850 miles from Bird 

 Key. Birds liberated at these places returned in a very short time to their 

 nests on Bird Key. The sooty terns returned from Cape Hatteras in 5 days, 

 and as they probably flew along shore and not by the straight-line route, they 

 must have flown at least 1,081 miles. This is a most striking experiment, 

 for Cape Hatteras is far to the northward of the northern limit of the 

 geographical range of these birds. 



