CROSWEL1. 1 



A 'A TURE- S TUD Y A ND SCIENCE NO TES 287 



carbons, which are so extensively used in the so-called diamond drill used in 

 cutting hard stones that within fourteen years the price has advanced from 

 $17 to $60 per carat. One carbon found in 1895 weighed 3,165 carats; 

 it sold at the mine for $16,000; when broken into pieces of 2 to 4 carats 

 suitable for drills it sold for $40,000; today it would bring $158,000. 

 [Popular Science Monthly, 69: 272, Sept., 1906.] 



The Oyster Industry. In the recently revised edition of "The Oyster," 

 by Professor Brooks of Johns Hopkins University, (published by the Univer- 

 sity, Baltimore) there are many interesting statements regarding the oyster 

 industry. Records have been kept since 1865 and since that time more than 

 four hundred million bushels of oysters have been taken from Chesapeake 

 Bay. The natural beds at present occupy two hundred square miles, but 

 five times this area is suitable for oysters and will ultimately be planted by the 

 oyster farmers. The author outlines what should be done towards making 

 the present beds as productive as formerly and extending the beds. 



Strength of a Beetle. A writer in a recent number of Nature 

 (London) notes a case where a beetle was able to lift up the edge of a box 

 which weighed more than 1700 times more than the insect. 



Age of Tortoises. A note in the September number of The Review 

 on the giant tortoise oi Galapagos Islands refers to the great length of time 

 required for these animals to reach adult size. I would call attention to notes 

 published by Mr. Edmund Heller in Proceedings of the Washington Academy- 

 of Sciences, Vol. 5. Mr. Heller (now of Field Columbian Museum) 

 spent twelve months in the Galapagos Archipelago and made careful observa- 

 tions on the species above mentioned. His observations on growth show 

 that a young specimen taken when twenty-nine pounds in weight doubled its 

 weight in twelve months. A specimen was brought to Riverside, California, 

 in a sack. In spite of the great change in climate the specimen has continued 

 to grow and when I saw it last summer (Aug. 1906) it had attained a 

 weight of 295 lbs., in seven years' time. The total shell length was over 36 

 inches. This may safely be considered adult size, as the largest specimen 

 Mr. Heller reports measuring in the Galapagos Islands was 1 1 5 centimeters 

 or about 44 inches. The Galapagos group is situated under the Equator 

 where there is little time during the year that the animals would not feed and 

 grow. In California there are some months of quiescence during the year 

 when no growth occurs. The impression that these animals grow at an 

 exceedingly slow rate seems then to be decidedly erroneous. The figures 

 now before us ought to correct that impression. 



State Normal School, LoYE HOLMES MlLLER. 



Los Angeles, Cal. 



