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SPONGES: RECENT AND FOSSIL. 
By Josep F. James, M. D., M. 8c., U. S. DEPT. AGRICULTURE, 
WasHinaTon, D. C. 
A sponge, while one of the lowest forms in the scale of ani- 
mal existence, belongs to a class ranging back in time almost 
to the beginning of organized life. Asknown in a living state 
it is an aggregation of individuals, each one minute, but to- 
gether forming a body often of considerable size. Without 
power of locomotion ; without any differentiation of parts such 
as obtain in animals of a higher grade, it yet manages to sub- 
sist in a great number of places and in the greatest variety of 
forms. Geology tells us the family has persisted upon the = 
earth since the earliest time of which there is any record; and 
at no period has it been absent from places suited for the 
growth of its various members. A few words about living _ 
sponges may make plainer a short account of some of the fos- 
sil forms. 7 
