NATIONAL FISHERY CONGRESS. 237 



prolonged nature than that of our own countrymen, it can not be said that their 

 results were as striking or encouraging. Their studies, which were supported by the 

 Austrian Government and merchants of Trieste, were finally abandoned, owing to the 

 hostile attitude and depredations of the fishing population. 



The following are some of the special facts that have been established by the 

 experiments in this country and abroad: 



(1) Sponges may be cut into small pieces, which will live and grow if properly 

 attached in suitable water. They may be cut in water or on a moistened board with 

 a knife or flue saw. Care must be exercised not to express the soft matter. The 

 preferred size of the cuttings is about an inch broad and a little more in height. 

 The outer skin is to be retained as far as practicable. In cutting, the lines of the 

 circulating canals should probably be considered, although pieces cut without any 

 reference to the direction of the canals have lived and grown. 



(2) Exposure of the sponge to the air in making and fixing the cuttings is not 

 injurious, unless prolonged or in very warm weather. This is contrary to a prevalent 

 impression, but seems to be amply proved. Mr. Munroe, in his experiments in 

 Biscayne Bay, found that clippings from sponges that had been exposed several hours 

 lived and grew; and in the Adriatic Sea sponge cuttings kept out of water, in a shady 

 place, for eight hours in February, the air temperature being 48 F., took root when 

 planted. It is probable, however, that in the case of larger sponges, when removed 

 from their element, the weight of the contained water may have a crushing effect on 

 the soft parts concerned in nutrition and thus retard growth in the clippings subse- 

 quently made therefrom. In a high temperature the sponges have a tendency to rot, 

 hence the winter is regarded as the best time for planting. 



(3) Clippings may be made from distorted sponges having little market value, and 

 will assume a symmetrical shape during growth. A healthy cutting will become 

 firmly attached to a surface comparatively soon if it does not move. Even as short a 

 time as 24 hours has been sufficient, in the European experiments, to secure attach- 

 ment during the prevalence of warm weather. 



(4) The possible methods of attachment are various. This is a very important 

 step, and probably the ideal practice is still to be determined. The thin'gs to be 

 accomplished are : (a) to make the clipping fast pending the time when it will naturally 

 take root; (b) to employ for this purpose some material that is not injurious to the 

 sponge and will not distort its growth; (c) to place the attached clippings on the 

 bottom in such a way that they will maintain the upright position and not be smothered 

 by mud, sand, or sediment. The sponge clippings have been attached to boards, 

 frames, poles, and different kinds of wire. The wooden parts are liable to attacks of 

 worms, and some kinds of wire are injurious because of the chemical decomposition 

 that ensues in salt water. The use of bamboo pegs seems to have given much 

 satisfaction. 



In Europe, the cuttings appear to have been placed at depths of 1C or 23 feet, light 

 being considered an objection, but in Florida the experiments have been conducted 

 in water from 8 feet to less than 1 foot deep at low tide, and good results have been 

 had at the shallowest depths. 



(5) The rate of growth in Florida waters is comparatively rapid. It is a common 

 experience of spongers to find marketable sponges on grounds that had been 

 thoroughly depleted of all salable sponges in the previous year, and the results of 



