226 



THE POPULAR SCIENCE MONTHLY 



Natives of the Murray Islands, Torres Straits. Wearing " Dahis.' 



the Ply River Delta type. 



Fapuans of 



was 30 inches in diameter in 1890 had increased to be 74 inches in 1913. 

 Also, a huge coral which Saville-Ivent called " Pontes astrceoides" was 19 

 feet in diameter in 1890 and 22 feet and 9^ inches in 1913. On the other 

 hand, a certain gray-green Gondastrea, which was 8 feet, 2 inches wide in 

 1890 had not grown during the intervening 23 years. Indeed, Dr. 

 Yaughan's growth experiments upon Florida corals show that perhaps 

 all corals grow to well-defined sizes and then cease to enlarge. However, 

 the corals that did grow at Vivien Point had increased in diameter from 

 44 to 45| inches in 23 years, or about 1.9 inches per annum. 



Thus charts of channels which are only occasionally used, and the 



