5 2 4 



THE POPULAR SCIENCE MONTHLY. 



dred putrefying corpses at a time to certain 

 holy places, often distant thirty or forty 

 days' travel. 



Spoages. Naturalists are now generally 

 agreed in classing the sponge with animals, 

 but place it in the very lowest rank of the 

 Protozoa, abutting on the vegetable kingdom. 

 Like a plant, the sponge grows on rocks or 

 other substances in water, being often found 

 attached to the shells of living crustaceans. 

 It consists of a gelatinous substance called 

 sarcode, and of a framework made up of 

 horny, elastic fibres (keratose), or of cal- 

 careous or siliceous spicules. The keratose 

 is the sponge of commerce, and its value 

 depends upon the elasticity and compressi- 

 bility of its fibres. 



The sarcode is sometimes represented to 

 be an amorphous mass of glairy substance, 

 but accurate observation with the micro- 

 scope shows, according to Huxley, that it is 

 constituted as follows : There is, first, an 

 external layer, continuous, and made up of 

 an aggregation of organisms with nuclei, 

 and much resembling amoebae. This stratum 

 is separated from another of identical 

 structure by a chamber filled with water. 

 The outermost layer has a multitude of 

 pores, through which the supply of food 

 and oxygen enters. The floor of the lower 

 and thicker layer has a number of orifices 

 opening into tubes which widen out into 

 globular caverns a little below the surface. 

 The sides of these globules are studded 

 with amoeba-like organisms, each having a 

 cilium, or appendage resembling an eye- 

 lash, which is constantly vibrating, and so 

 establishing a current in a direction down- 

 ward into canals which open into great, fun- 

 nel-like, or crater-like orifices. These great 

 orifices are the exhalant apertures, the pores 

 inhalant apertures. The food and oxygen 

 in the stream of water is appropriated by 

 the sponge-organisms individually as it 

 flows by. 



When placed under the microscope, the 

 living sponge is a wonderful sight. Dr. R. 

 E. Grant, who was the first to witness it, 

 having put a small branch of living sponge, 

 with some sea-water, into a watch-glass, 

 saw a " living fountain vomiting forth from 

 a circular . cavity an impetuous torrent of 

 liquid matter, and hurling along, in rapid 



succession, opaque masses, which it strewed 

 everywhere around." Here is a circulation 

 of water answering the same purpose as 

 that of blood in other animals. The sponge 

 takes in food and oxygen through its mi- 

 nute pores, and voids the waste matter 

 through the oscula, or larger orifices. In 

 the Spongia Jluviatilis, or fresh - water 

 sponge, the pores are not permanent, but 

 they appear and disappear without leav- 

 ing a trace behind, as in the case of the 

 amoebas. 



The spicules of the siliceous sponges as- 

 sume sundry shapes, being sometimes 

 straight, like needles ; again headed and 

 pointed like pins, or furnished with grapnel- 

 like hooks at their ends, etc. Perhaps the 

 most curious of all the sponges is the 

 "glass-rope" (Hyalonema), which has the 

 appearance of a rope of twisted glass 

 fibres, with a fibrous sponge attached to one 

 end. Another very interesting form of 

 sponge is the Eupledella speciosa, or Venus's 

 flower-basket, which grows in the shape 

 of a cornucopia, and is composed of fine 

 glossy threads of silica. 



The best sponges for toilet use come 

 from the iEgean, and are found in about 

 eight fathoms of water. They are gath- 

 ered by divers. A coarse quality of sponge 

 is found on the coasts of Florida and the 

 West Indies. These are gathered with 

 long-hafted forks. To remove the sarcode, 

 the sponge is buried for some days in the 

 sand, until the animal matter rots, and then 

 the horny keratose is soaked and washed. 



Jatc-Paper. One day's issue of the 

 Dundee (Scotland) Advertiser was recently 

 printed on paper made of jute. The mate- 

 rial is said to be of good, firm quality, 

 though thin and transparent, and of a yel- 

 lowish tinge. The chief objection hitherto 

 urged against jute-paper is its dark color ; 

 and, if, as appears probable, this can be ob- 

 viated, there is no doubt that jute-paper 

 will quickly supersede that made from rags, 

 except for the best qualities. The jute em- 

 ployed in this instance is old bagging, which 

 commands but a low price. As an encour- 

 agement to inventors, the proprietors of the 

 Advertiser offer a premium of 50 for the best 

 ream of paper made entirely from jute, of the 

 size and weight of the paper on which the 



