470 



SCIENCE 



[N. S. Vol. XXXII. No. 823 



following : " The Formation in the Animal 

 Body of Z-/3-0xybutyric Acid by the Eeduc- 

 tion of Aceto-acetic Acid," by H. D. Dakin. 

 Experiments are described which show that 

 the liver possesses a mechanism, dependent 

 upon the antagonistic action of two ferments, 

 by which the mutual interconversion of /J- 

 oxybutyric acid and aceto-aoetic acid may be 

 effected. It is thought probable that the ji- 

 oxybutyric acid which appears in the blood 

 in acidosis is the result of reduction of aceto- 

 acetic acid in the liver. The mechanism of 

 the reactions involved is discussed. " On 

 Decomposition of Aceto-acetic Acid by En- 

 zymes of the Liver : Part II.," by A. J. Wake- 

 man and H. D. Dakin. The primary product 

 of the action of the enzyme in the liver which 

 has been showa to decompose aceto-acetic acid 

 is Isevo-rotatory /J-oxybutyric acid. " The 

 Products Eesulting from the Putrefaction of 

 Eibrin by Clostridium carnofeetidus, Salus 

 and Eauschhrand," by Erancis H. McCrudden. 

 Analyses show that distinct differences exist 

 between the putrefactive products of the 

 organisms named which may be of diagnostic 

 value. " The Metabolism of Some Purine 

 Compounds in the Dog, Pig and Man," by 

 Lafayette B. Mendel and John F. Lyman. A 

 comprehensive, comparative study of the fate 

 of various purines in the organism. " A 

 Study of Enzymes by Means of Synthetical 

 Polypeptids," by A. H. Koelker. Eacemic 

 alanyl-glycin may advantageously be used in 

 the study of proteolytic enzymes. The rate 

 and extent of digestion can be easily estimated 

 by the optical method. 



SPECIAL ARTICLES 



FDETHEE DATA ON THE HOMING SENSE OF NODDY 

 AUD SOOTY TEENS 



DuEiNG May and June of the present year 

 I continued my studies on distant orientation 

 in the noddy and sooty terns at the Tortugas 

 colony. The report of the work done in 1907 

 will be found in publication 103 of the Car- 

 negie Institution. The work in 1910 like that 

 in 1907 was done under the auspices of the Ma- 

 rine Biological Laboratory of the Carnegie 



Institution. I wish to thank Dr. Mayer, of 

 the laboratory, for his continued kindness to 

 me during the past season's work. 



The 1910 season was one very unfavorable 

 for conducting experiments upon distant 

 orientation. The spring was late in the north- 

 ern temperate regions, and this, combined with 

 the severe storms in the Gulf, seriously handi- 

 capped the work. It was often impossible to 

 get birds to Key West in time to make connec- 

 tions with the Mallory steamers. The water 

 between Tortugas and Key West is often very 

 rough, and unless there happens to be a flat 

 calm we never attempt to go to Key West in 

 our small launches. Several times our experi- 

 ments had to be given up for this reason, even 

 after the birds had been captured and marked. 

 Then, too, after every important release 

 (Galveston, New York and Mobile) adverse 

 winds set in against the birds. 



By far the most serious defect in the work 

 was the failure until towards the very last to 

 perfect a favorable technique for shipping 

 and feeding the birds. In 1907 the orienta- 

 tion work was incidental. In 1910 it was the 

 principal feature. For this reason it was de- 

 sired to make large shipments. The method 

 adopted in all cases was to capture and mark 

 about twelve to fourteen birds, put them into 

 one large hooded cage and give them in charge 

 of a capable employee of the laboratory, who 

 would accompany them on the trip and re- 

 lease them at the proper time. Minnows, when 

 they could be obtained, were purchased in Key 

 West and put in the ice chest of the Mallory 

 boat. At times when they were not obtainable, 

 large fish were carried and cut up into small 

 pieces and fed the birds in the place of min- 

 nows. This latter method is not nearly so 

 satisfactory, since many of the birds will re- 

 fuse chopped fish when they will not refuse min- 

 nows. The most serious mistake made was in 

 sending too many birds in one cage. They could 

 not be given individual attention. Many died 

 on the way, either from starvation or else were 

 trampled to death. The birds apparently 

 have an instinctive tendency to perch. Some 

 get seriously lacerated through having others 

 climb up and perch upon them. In carrying 



