518 



SCIENCE 



[N. S. Vol. XXIX. No. 743 



every arm is more rapid the greater the number 

 of arms removed yet this regeneration is carried 

 on at the expense of the normal body tissues 

 wnich shrink while the arms grow, thus recalling 

 the case of cancerous growths which, having more 

 ability to absorb nutriment than the normal body 

 tissues, grow at the expense of the body itself. 

 Stockard finds also that the nearer the cut sur- 

 face is to the center of the disk of the medusa 

 the more rapid the regeneration. He finds that 

 regeneration is somewhat retarded by a slight 

 excess of NaCl, very much retarded by CaClj, but 

 not appreciably affected by Mg. A slight excess 

 of KCl accelerates, and a strong excess retards 

 regeneration. Zeleny, working upon the gulf- 

 weed crab, Portunus sayi, finds that successive 

 removals of appendages neither increase nor de- 

 crease the rate of regeneration of the successively 

 removed part. 



"An interesting series of observations were 

 carried on by Dr. Stoddard in which he shows that 

 the habits of the walking-stick-insect, Aplopus, 

 accord perfectly with the general resemblance of 

 the animal to a stick. He discovered that the 

 males will mate with the cut-oflF terminal part 

 of the female's abdomen if this be mounted upon 

 a stick. 



" Professor Jacob Reighard, of Michigan Uni- 

 versity, investigated the problem of ' warning 

 coloration' in so far as it affects the brilliantly 

 colored reef fishes and their enemies, and he shows 

 conclusively that these brightly colored fishes are 

 at once greedily devoured if they leave the shelter 

 of the coral reefs. The commonest predatory fish 

 of the Tortugas, the gray snapper, Lutianus 

 griseus, can, however, be taught to avoid a fish 

 rendered artificially distasteful, and will remem- 

 ber its experience and still avoid the possible 

 prey for at least twenty days after it has had the 

 evil experience of attempting to devour such a 

 fish. The coral-reef fishes are, therefore, not 

 warningly colored, yet warning color could exist, 

 but apparently it does not in nature; at least in 

 so far as the reef fishes experimented with are 

 concerned. 



" Professor John B. Watson, of Johns Hopkins 

 University, remained for three months upon Bird 

 Key, Tortugas, studying the reactions of the noddy 

 {Anodus stolidus) and sooty {Sterna fuliginosa) 

 terns. This work was conducted under conditions 

 of great inconvenience, for the temperature of the 

 air under the bushes is commonly 123° F. at noon. 

 Professor Watson found about 1,400 noddies, and 

 18,800 sooties nesting upon this little island not 



a quarter of a mile wide. While the noddy is 

 building its nest in the bushes early in May it is 

 very shy, but as soon as the egg is laid its habits 

 change and it will remain and defend the egg. If, 

 however, an egg be artificially placed in an unfin- 

 ished nest the habits of the birds at once change 

 and they settle down upon the egg and defend it. 

 They do not recognize their own eggs, and will 

 sit upon hens' eggs, sooty terns' eggs, their own 

 eggs painted red, green or black, or an artificially 

 egg-shaped piece of magnesium sulphate. The 

 sooty tern, however, will not usually accept col- 

 ored, or strange-looking eggs. The noddies relieve 

 each other on the nest at intervals of about two 

 hours, the new-coming bird crowding the sitting 

 mate off the nest. 



" The sooty tern makes its nest upon the 

 ground. It is greatly confused and may lay a 

 new egg if the egg be moved twenty-two inches 

 horizontally from the original place, but the egg 

 may be raised or lowered many feet in a vertical 

 direction and the bird alights upon it at once 

 apparently undisturbed. 



" The young birds of both species can be taught 

 to go through a labyrinth for their food; and 

 the old sooties can learn to go through a maze 

 to their egg, or to open a cage to obtain access 

 to the egg. Neither of these birds is in the habit 

 of going more than about seventeen miles from 

 the island for their supply of fish, yet when they 

 were taken away in the holds of vessels and lib- 

 erated at Key West, Havana and Cape Hatteras 

 they returned to the island. In the case of the 

 sooties, the return from Cape Hatteras to Bird 

 Key was made in five days, the straight-line dis- 

 tance being 850 and the ' along-shore ' route 1,081 

 statute miles. There are many other important 

 observations recorded in Professor Watson's paper. 



" The lecturer expressed regret that limitations 

 of time prevented his presenting before the acad- 

 emy the results of other interesting studies which 

 had been conducted by investigators at Tortugas, 

 but would refer his audience to the papers of 

 Jennings, Linton, Perkins and others who had 

 published accounts of their researches at the 

 laboratory." 



The paper was discussed at considerable length 

 by C. Hart Merriam, Austin H. Clark and T. S. 

 Palmer, who heartily commended the work of the 

 Tortugas laboratory, and referred to similar labo- 

 ratories and their work in various parts of the 

 world. 



J. S. Dilu:b, 

 Recording Secretary 



