126 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



used, which, while slowly acted upon by salt water, lasted a sufficient 

 length of time to permit the sponge to permanently heal. 



During the winter months the growth of the cuttings was rather 

 slow, so far as increase in bulk was concerned, although e3"es, or oscula, 

 were promptly put out and the circulatory system quickly reorganized 

 and completed. During the spring when the water, especially in the 

 more southern part of the State, was becoming warmer, there were 

 indications of more rapid growth. About six thousand cuttings were 

 planted in Biscayne Bay, Sugar Loaf Kej^ and in the vicinity of 

 Anclote Keys, and in the latter part of April, after they had been 

 planted for periods varying from two to five months, most of them 

 were growing and in an apparently healthy condition. 



Between the lower end of Biscayne Bay and Matecumbe Kej' there 

 is a long stretch of water where sponges do not grow naturally. An 

 investigation of this region was made to determine the reason for 

 their absence, and an experimental plant of about a thousand cuttings 

 was made in a small sound back of Key Largo, with a view to deter- 

 mining whether they could be artificialh^ introduced there. At the 

 end of six weeks practicall}^ all of these cuttings were dead, although 

 others planted at about the same time in more favorable localities 

 were alive and growing. A series of observations developed the fact 

 that the water in this region is of a much lower salinity than in places 

 where the sponge grows naturally, and it is probable that this is the 

 cause of their absence naturally and of the mortality of the cuttings. 



Practically nothing is known of the rate of growth of sponges under 

 natural conditions, or of the rapidity wdth which they will develop 

 from fragments and cuttings, and it will probably require several years' 

 investigation to determine these points and to develop, if it can be 

 developed, a system of sponge-culture which will be of value to the 

 State of Florida. At the present time the production of sponges in 

 this State, which is the only one in the countrj-^ producing them, is 

 about $500,000 per annum. An equal or perhaps greater value of 

 sponges is imported from abroad, and it is hoped eventually to supply 

 this excess of demand over production by sponges raised artificially. 

 Many of the sponge-dealers are showing considerable interest in the 

 experiments, and it is believed that thej^ will promptly undertake 

 sponge-culture if a reasonably practical method can be developed. 



SURVEY OF THE FLORIDA SPONGE-GROUNDS. 



The steamer Fish Ilaioh, working under the direction of this divi- 

 sion, in October, 1901, resumed the survey of the sponge-grounds of 

 the western coast of Florida, and in March, 1902, completed the exam- 

 ination of the waters lying north of Tampa Bay, comprising all those 

 grounds designated under the names "Gulf," " Bay," "Rock Island," 

 and "Anclote." The location of the sponge-groiuids has been plotted 



