47 



Sheep's-wool variety, but the texture is denser and yields 

 only to a considerable pressure of the fingers, and they are, 

 consequently, of much less commercial value. This variety 

 is not found in the shallower water, being usually collected 

 from a depth of over sixteen feet. Its habit of growth is more 

 isolated than that of the Sheep's-wool. A height of six, with 

 a diameter of from sixteen to twenty inches, represents the 

 largest examples of this type that have been so far observed. 

 Numerous coarser sponges, not suitable for toilet use, but 

 at the same time of marketable value for outdoor purposes, 

 are obtained in large quantities from the Bahama waters. 

 Among these are included the so-called Velvet, Abacco- 

 velvet, or Boat-sponge (S. eqiiina, var. inea7idriniformis), 

 differing from the Sheep's-wool in the absence of the fleece- 

 like tufts upon its outer surface, these being replaced by pro- 

 truding softened cushions of fibre which somewhat resemble 

 the convoluted ridges of the well-known " Brain coral " 

 {Meandrind). Another variety of the coarse-fibred series 

 is the Grass-sponge (5. equina, var. cerebriformis) ; it in 

 many respects resembles certain varieties of the Reef-sponge 

 {S. agaricind), but may be distinguished from such varieties 

 by the character of the general surface. This is broken up 

 on the sides by parallel longitudinal ridges of irregular 

 length, each of which are ornamented by longitudinal lines 

 of tufts. These ridges are continued upon the upper surface, 

 and give to this region a distinctly radiate pattern. The 

 larger orifices or oscula are disposed in rows in the channels 

 between the longitudinal ridges. A second form — which is 

 likewise included among the so-called Grass or Glove 

 sponges — has been figured and described by Mr. A. Hyatt 

 under the title of Spongia graminea. While somewhat 

 resembling the Glove-sponge (6". officinalis, var. tiibulifera) 

 previously described, its texture is much coarser, and its 



