88 



The Supplement to the Tropical Agriculturist 



ARTIFICIAL CULTIVATION OF 



SPONGES. 



U. S. A. COMMISSIONER'S SUCCESS. 

 Pkivate Co. Organised : Method Explained. 



Washington, Oct. 22, 1909.— The United States 

 Commissioner of Fisheries in his coming annual 

 report will make the interesting announce- 

 ment that the work of the bureau in testing the 

 practicability of the artificial cultivation of 

 sponges has reached a point justifying com- 

 mercial exploitation of the bureau's methods on 

 a large scale. The commissioner will say : — 



" Such progress has been made in experimental sponge 

 culture at certain points on the coast of Florida that the 

 bureau is now in position to recommend the growing of 

 sponges from cuttings as commercial enterprise, and will 

 shortly make public the methods and outcome of the experi- 

 ments that have extended over a series of years. The 

 outcome of the past season's operations has been the 

 production of marketable sponges, and of an average 

 weight of one-and-aquarter ounces, in twenty-nine months. 

 It is understood that a private comp iny has already been 

 organised to carry on sponge culture on a commercial 

 basis, following the methods made known by the bureau; 

 and it is believed that very important economic results 

 must accrue to prospective sponge planters, while at the 

 same time the stability of the sponge crop is assured." 



The work of the Bureau of Fisheries in the 

 artificial cultivation of sponges has been 

 conducted by Dr. H. F. Moore. These are 

 the only tests ever made in the history of 

 the industry either here or abroad that pro- 

 mised to be of commercial importance, and 

 were undertaken in January, 1901, at Sugar 

 Loaf Key, and at other places in Biscay ne 

 Bay, Fla, Growing from cuttings was adopted 

 because of its simplicity and the certainty 

 with which the cuttings will attach and re- 

 generate when placed under suitable conditions. 

 After numerous experiments it was finally es- 

 tablished that pieces about 1| by 2 by 2i incheR 

 were most suitable. These cuttings were placed 

 on wires formed by various materials, each 

 piece being slit by a sharp knife, and fastened 

 astride the wire by a bit of aluminium wire. 

 In about six weeks after submergence in the 

 sea the cuttings have been found to heal, an 

 outer skin formed over the entire cutting and 

 a slow but steady growth begun. Various kinds 

 of wire have been used and abandoned for 

 various reasons. The greatest measure of suc- 

 cess in the growing of sponges suspended in 

 the water has followed the use of a galvanised 

 iron ribbon three-eighth s-of-an-inch wide and 

 one-sixteenth inch thick encased in a tight fitting 

 jacket one-thirty-second of an inch thick. The 

 ribbon obviates the difficulty encountered in 

 the use of a round wire when the sponges reach 

 five inches in diameter, when they are loos- 

 ened by the action of the waves and begin to 

 rotate, thus wearing large holes which damage 

 them commercially and retard their growth. 



In many localities, however, the growing of 

 sponges on wires suspended in the water has 

 been found less practicable than to mount the 

 cuttings on flat discs or triangles made of cement. 

 These cement forms can be made at an expense 

 of less than two cents each, including labour 

 and material. The cuttings were attached by 

 means of a wire. On some grounds, where 

 strong currents were encountered, resulting in 

 some shifting of sand and silt, which threatened 

 to bury the disc and cutting it, it was found 

 desirable to mount the cutting on a spindle 



made of a short length of the lead covered iron 

 ribbon. The use of discs and triangles, all things 

 considered, would appear to promise better 

 success on a commercial scale thaD the method 

 of suspending the cuttings on ribbon wires, but 

 much depends on the character of the bottom, 

 the prevailing currents and other considerations. 



Under artificial culture the shapes of sponges 

 may be modified more or less to suit the special 

 requirements of the arts. Sponges grown on 

 wires or spindles assume a spheroidical shape 

 with a uniform texture of surface and devoid of 

 any semblance of a "root" such as is found in 

 all natural sponges excepting rollers. This form 

 is very attractive and durable. 



Cuttings grown on discs tend to assume a 

 Hatter shape, and the surface attached to the 

 cement is plane, and in that respect resembles 

 the root of natural sponges, but instead of being 

 "raw" and exposing the canals, it is covered 

 with a close soft felt of great strength and dura- 

 bility, and forms the strongest, instead of the 

 weakest, part of the sponge. 



In certain arts and trades sponges with flat 

 surfaces are required, and to obtain these it is 

 customary to cut the "forms" into pieces. The 

 raw surfaces exposed in this way lack the dura- 

 bility of the natural surfaces and to obtain the 

 latter style at the same time retaining the seve- 

 ral flat faces and sharp angles of the "cuts" a 

 modified form of disc is employed. In these 

 there are two partitions raised to a height of 

 four inches crossing one another at right angles 

 on the upper surface of the disc. This leaves at 

 the centre of the disc four angular compart- 

 ments, and in each of these a cutting is planted, 

 which being limited on three sides by the disc 

 and partitions, grows into a form having three 

 plane surfaces at right angles to one another 

 and one convex surface. The latter is similar 

 in texture to the outside of an ordinary sponge, 

 but the plane faces form contact with the disc 

 and partitions and develop a smooth, soft and 

 very durable felt-like surface. These sponges 

 cost more to grow than those of ordinary shape, 

 but experiments recently inaugurated will pro- 

 bably make the additional cost of production 

 trifling. The superior durability of sponges 

 grown in this manner will make it possible to 

 market them at a price considerably above that 

 brought by the natural product. — New York Oil 

 Reporter, Oct. 25. 



EXPERIMENT STATION IN SUMATRA. 



To Devise Means to Cope with the Diseases 

 which Attack Rubber Trees. 



Rubber planters in Deli have agreed to estab- 

 lish an experiment station there. The prelimi- 

 nary outlay is set at 30,000 guilders, spread 

 over three years. It is intended to engage a 

 botanist learned in biology who, after gaining 

 experience in Ceylon, the Straits Settlements, 

 and Java, will at once set to work to devise 

 means to cope with the diseases whinh attack 

 rubber trees. Contributions to meet the outlay 

 are expected from every estate according to 

 the area. The number of estates is about 80 

 spread over about 30,000 acres. Twenty-two 

 planters have fallen in with the idea and a 

 Committee has been appointed to settle the 

 details. — Straits Times, Dec. 3. 



