46 



value being nearly, if not quite, equal to that of the Turkish 

 form. Like the ordinary honeycomb type, it usually ex- 

 hibits a sub-spheroidal form of growth, its inner substance 

 being honeycombed in every direction by sinuous intercom- 

 municating channels, and the large excurrent apertures, or 

 oscula, being distributed with comparative regularity 

 throughout its superficies. A characteristic external 

 feature, which readily distinguishes this sponge from its 

 Mediterranean homotype, is supplied by the peculiar tuft- 

 like manner in which the fibres of the external surface of 

 the skeleton are produced in the interspaces between the 

 oscula, and which latter structures are consequently found 

 occupying more or less deep depressions. It is this tufted 

 development of the superficial skeleton that imparts to the 

 sponge that fleecy aspect from whence it derives its popular 

 title. The habitat of the Sheep's-wool sponge is depths 

 varying from three to as much as sixteen feet and deeper, 

 its precise limits not having yet been ascertained. The 

 largest and finest-fibred examples are obtained at the 

 greatest depth, these not unfrequently measuring as much 

 as twenty or thirty inches in diameter, with a height of 

 eight or nine inches. It is a peculiarity, however, of these 

 extraordinary large specimens that the centre portions of 

 their tissue become tender and disintegrated, leaving an 

 outer ring-shaped area of the sponge alone intact. Several 

 remarkably fine samples of such huge ring-shaped Sheep's- 

 wool sponges are now on view in the Bahama section of 

 the Exhibition. 



The third type, coinciding most nearly with the Zimocca 

 variety of the Mediterranean sponges, is represented in the 

 Bahama Seas series by what are known as the Hard-head 

 or yellow sponges {Spongia agaricma, var. corlosia dura and 

 punctata). In some respects they nearly resemble the 



