TWELFTH ANNUAL REPORT g7 



is a shallow-water species, the supply will soon be exhausted 

 unless a law is passed to prohibit the gathering of the young. 

 Hundreds of young shells which are too thin to be made into 

 buttons can be seen at the button factories where they are thrown 

 out as useless. If they had been allowed to grow two more years, 

 they would have been valuable. 



For the first time in the history of the Islands the "scope" 

 or "ear" pearl-shell (Avicula microptenis L.) is being gathered 

 and made into buttons. This shell was considered of no value 

 until Mr. Seale called the attention of the button manufacturers 

 to its utility. 



The desirability of taking the control of the pearl beds in the 

 Christian provinces from the municipalities and placing it under 

 the Department of the Interior is strongly urged. These beds 

 should be charted, and an alternate third of them closed each 

 year in order to maintain the pearling industry and allow the 

 shells to mature. 



Fish culture. — The black bass in the Baguio and Trinidad 

 ponds have multiplied in a most satisfactory manner, and this 

 season saw the inauguration of the first black-bass fishing in 

 the Islands. According to regulations issued from the Depart- 

 ment of the Interior, bass over 25 centimeters in length may be 

 caught by fly fishing provided that all fishes under this length 

 are promptly returned to the water. The fees charged are used 

 to pay wardens. Bass were successfully transferred in Decem- 

 ber to the spawning ponds at Los Bahos, where they are all 

 alive and in fine condition and where they will probably spawn 

 within the next three months. 



Two dozen mosquito fish (Gambusia affiiiis) were brought 

 from Honolulu on January 3, 1913. These were placed in an 

 aquarium, in the section of ichthyology, where they have mul- 

 tiplied rapidly. Two hundred have now been planted in the 

 swamps and fish ponds in the vicinity of Manila, and a stock of 

 perhaps 100 still remains on hand. By actual count one of these 

 little fish ate 500 mosquito larvse in twenty-four hours; there- 

 fore, these fish are of direct importance to the public health, 

 and their cultivation is worth our best efforts. 



Scientific work. — A paper on the fishes of Hongkong, giving 

 descriptions of several new species, is nearly completed, and 

 a paper, The Edible Mollusks of the Philippines, was issued 

 during the year. The identification of a number of small col- 

 lections of fishes from various and numerous localities which 

 have. been sent in during the past year will be finished within 



