grading purposes, these have to be described separately. This group 

 has the scientific name of Hippiospongia lachne . 'When picked, the 

 sponges in the group are drab to black and have a tough, smooth skin 

 and many connected channels inside. The cleaned wool sponge, if 

 examined with a strong lens, shows the parallel fibers present in 

 all the commercial sponges but shows the cross fibers as being smaller » 

 more abundant, and attached at angles approaching the parallel fibers. 

 The colors cover the same range as do those of tanned leather, al- 

 though occasionally, gray or rusty red variation occur, with the color 

 being more concentrated in the base of the sponge and practically never 

 working through to the surface. Such a red color is considered to be 

 a fault. A very pale sponge may indicate artificial bleaching, where- 

 as a very dark sponge usually indicates poor removal of gurry. Such 

 uncleanliness is detected easily by an unusual stiffness when the 

 sponge is dry and by a strong odor and milky wash water when the sponge 

 is wet. 



Inshore and Rock Island 



Inshore- type sheepswool sponges (figure 1) are considered by 

 scientists to be merely environmentally conditioned variations of the 

 Rock Island sponge (figure 2). Original ly, the tradesmen thought that 

 the name was appropriate as indicating a relatively sharp division in 

 the depth of collection; but many are convinced, by overlapping ex- 

 amples from both types, that the Inshore type is the result of factors 

 of growth other than depth of water. 

 Nevertheless, reclassification by 

 the trade would be difficult to ef- 

 fect, so the present report did not 

 eliminate samples of Inshore sponges 

 when submitted for Rock Island tests* 

 The tests on Inshores, however, were 

 made after a few obvious Rock Island 

 samples had been removed from the 

 lots tested. 



The actual division used by the 

 trade at present is based almost en- 

 tirely on the fact that Rock Island 

 sponges are collected primarily by 

 diving boats and that Inshore sponges 

 are collected primarily by non-di v i n g 

 or hooker boats, which are smaller 

 and collect closer to land with the 

 aid of hooks on long poles. 



Figure 1.— Inshore Sheepswool 



The Inshore type of sponge differs from the Rock Island type with 

 intermediate degrees being quite common, by having more large internal 

 holes and therefore a softer feelj and especially by having, on the 

 surface, fine tufts or feathers, which often are curled. This feathery 



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