306 SUMMARY OF CURRENT RESEARCHES RELATING TO 



boat must bo used, to approach the floating, submerged, or dependent 

 sponge-bearing substances. A large, strong knife or paper-hanger's 

 scraper will be found convenient for hand work at short range. _ A case 

 containing trays an inch or so in depth is] suitable for carrying the 

 smaller specimens ; the larger will of course require vessels of greater 

 size. On reaching home it is well to select some specimens of charac- 

 teristic shapes, and containing gemmules, for storage in dilute alcohol, 

 making use of wide-mouthed bottles to avoid crushing them. The rest 

 may be spread upon boards in sheltered situations, in the shade (for the 

 sua bleaches them rapidly) and left to dry; turning them every few 

 hours to prevent decomposition. If time is limited or the specimens are 

 large, artificial heat may bo necessary ; but whatever process is used, 

 the drying must be thorough, or mould will soon cover the sponges with 

 a mycelium which may be beautiful enough in itself, but is far from 

 agreeable or sightly as a feature of the sponge. Whether they are to be 

 dried or preserved in alcohol, they should be dealt with promptly, and 

 on no account left to lie long in the water after being gathered. Preserve 

 from dust in covered boxes. 



Unless the sponges are large, it is difficult to detach them without 

 mutilation from the rough surfaces of stones. It is therefore preferable 

 to gather, when possible, those growing upon wood, which may be 

 scraped or chipped without injury to them. It is essential to secure the 

 very lowest portions, as it is there the gemmules often abide. 



The proper season for collecting fresh-water sponges, in waters of 

 the temperate zone, depends upon the purpose of the collector. If it 

 is his desire to gather cabinet specimens merely, for the identification of 

 old, or the determination of novel species, it is hardly worth while to 

 begin before July. As with the flowering of plants, the maturity of 

 different species of sponges is attained at various dates between mid- 

 summer and late in November. The essential point is that the gem- 

 mules and their armature shall be fully perfected; and when that 

 condition is attained in any specimen, there is no reason for further 

 delay. 



The author would, however, "recommend to intending students a 

 far higher object for their ambition — that is, the study of the physiology 

 and life-history of sponges, as members of a sub-kingdom whose position 

 has been greatly questioned, and whose character, derivation, and sub- 

 sequent evolution are very important and perplexing topics." He would 

 have such workers search for and examine them at all seasons of the 

 year (even in midwinter, when he has never failed, in suitable situations, 

 to find some in a growing condition), keeping memoranda as to each 

 species separately, noting the date of their germination or earliest 

 appearance, the location, elevation, and temperature, rapidity of growth 

 at diiferent seasons, time and manner of formation of gemmules, stability 

 or decadence during the winter, modes of distribution and progression, 

 whether always down stream or by other more adventitious methods, 

 what becomes of the gemmules upon reaching salt water, and the 

 thousand and one problems that go to make up the life-history of any 

 animal form, and that in this instance have been very little studied. He 

 is particularly anxious that some competent person should undertake 

 their study in the briny, brackish, and the fresh-water lakes pertaining 

 to what is known as the " Great Basin of the West," with a special view 

 to ascertain the conditions under which they form " protected gemmules " 



