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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1864. Excerpt: ... Sponges. Remarks on Classification--Structure of a Sponge--JTaturalists who have contributed to the history of Sponges--Chemical nature of Sponge--Interesting results--Spongia officinalis and S. usta--The Syrian toilet Sponge--Its high price--Other Sponges--Objects for the Jlquarium--Spongilla fiuviatilis and S. lucustris, or the fresh-water Sponges--Sponges common on the English Coast--Their use in Jdedicine--Sources of Iodine and Piromine--Flints and Jlgates, as owing their formation to Sponges--(Petrified Sponges--(Practical details on the toilet Sponge--Sponge Fishery and Sponge JAarkets. SPONGES. HAVE placed Sponges in my last chapter, and in doing so I am apparently following the old zoological routine, which regards these singular beings as the last link of the animal chain--the link which joins the animal to the vegetable world; but this surely is not a fact! Sponges are evidently more closely allied to Polypes than to such animalcules as the Monads. Indeed, had it been practicable, I would willingly have condensed Polypes, Infusoria, and Sponges into one chapter. But the reason why Infusoria have been lately placed before Sponges by most zoologists appears to be, that as the former class becomes better known, and the organization of its species more thoroughly investigated by means of the powerful microscopes constructed at the present day, the complication of their structure excites astonishment, and, as we have already seen, many genera are being placed much higher in the series than the places which were formerly assigned to them. In the same way many Infusoria will probably, one day, be classed below Sponges. We must look upon a vast number of these microscopic beings as a group of animals under discussion. Proper places will be assigned to t...
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