738 MARINE PRODUCTS OF COMMERCE 



Chemistry 



Sponges of the markets consist principally of spongin, an albuminoid related 

 to conchiolin found in the shells of mollusks, and fibroin and sericin, the principal 

 constituents of silk. Its composition is reported to be: 



C 46.50 H 6.30 N 16.20 S 0.50 ( Croockewitt ) 

 C 48.75 H 6.35 N 16.40 (Posselt) 



In 1898 Hundeshagen demonstrated the occurrence of iodine and bromine in 

 organic combination in different sponges, and designated the albuminoid contain- 

 ing iodine, iodospongin. Harnack (1898) later isolated from the ordinary sponge, 

 by cleavage with mineral acids, an iodospongin which contained about 9 per cent 

 iodine and 4.5 per cent sulfur. On the acid hydrolysis of spongin Abderhalden and 

 Strauss (1906) obtained 18.1 per cent glutamic acid and 13.9 per cent glycocoll, 

 as well as 7.5 per cent leucine, 6.3 per cent proline, and 4.1 per cent aspartic acid. 

 By the use of dilute acids Strauss (1905) has obtained sponginoses of various 

 kinds from spongin. The heterosponginose contained the greater part of the iodine 

 and sulfur, while the deuterosponginose contained the carbohydrate groups. 

 Iodospongin is considered a derivative of the heterosponginose. 



More recent studies identified the iodine compound obtained from spongin as 

 di-iodo-tyrosine, a complex which also contains bromine. The physiological role 

 the iodine plays in sponges is not known. 



No complete analyses of entire sponges, with the fleshy matter in situ, appear 

 to have been published. The Bureau of Soils, U. S. Department of Agriculture, 

 investigated the organisms as sources of fertilizer, and found that an air-dry horny 

 sponge contained moisture 13.90 per cent, silica (SiO„) 1.41 per cent, nitrogen 

 7.41 per cent, phosphoric acid (Pg^s) ^-^^ V^^ cent, and potash (KgO) 1.64 

 per cent. 



Sponge Culture 



In 1785 F. Cavolini, an Italian, made the observation that pieces of living 

 sponges would attach to foreign bodies and grow, and in 1862 Oscar Schmidt 

 repeated the observation and suggested that it offered the basis for developing 

 a method of sponge culture. The suggestion was taken up in 1867 by certain 

 merchants of Trieste, who established an experiment station. Since then experi- 

 ments have been conducted by Munroe, Harris, Dubois, AUemand-Martin, and 

 others in the Mediterranean, and by the government of the Bahama Islands. The 

 essential procedure of all of these experiments has been to cut the living sponge 

 into pieces, which were attached in various ways to different kinds of supports. 



The method finally adopted by H. F. Moore was to fasten pieces of 8-inch 

 sponge to cement discs about an inch thick and 10 inches in diameter, attachment 

 being made by means of an aluminum wire thrust through the sponge and passing 

 through a hole in the disc. Information concerning this method and others and 

 a more complete history of the subject may be found in papers cited in the 

 bibliography. 



These methods were tried on a commercial scale at Anclote Key and Sugar 

 Loaf Key, Florida. At the former location the sponges were killed by an influx 

 of fresh water, and at the latter the project was abandoned for reasons other than 

 technological and biological. 



