36 
GUIDE TO THE CORAL GALLERY. 
High Cases 
I. II. and 
Table Case 1. 
of commercial sponge, has a flat disk-shaped body with numerous 
oscules on the upper surface. 
The Levant Lappet, which is a variety of Spongia officinalis , 
forms huge thin flaps like an elephant’s ear ; occasionally the edges 
of the flap unite to form a capacious funnel-shaped cup. 
The above three species (S. officinalis , S. zimocca , and H. equina) 
include numerous varieties and variations which need not be further 
alluded to here. 
Commercial Sponges flourish in sub-tropical and tropical waters in 
depths of 2 to 100 fathoms, the world’s supply coming almost entirely 
Fig. 19. 
Section of Hippospongia equina, the Common Bath Sponge. (Natural size.) 
from the West Indies and eastern half of the Mediterranean. In the 
latter region they are collected by divers, who descend naked or in 
diving-dresses, or by men who hook up specimens by means of a 
long harpoon ; dredges are employed in deeper waters. In the West 
Indies (Florida, Bahamas, &c.) the hooking method is employed, a 
bucket with a pane of glass in the bottom being used as a submarine 
spy-glass to do away with the effect of the surface ripples. 
Sponges are prepared for market by macerating them in sea- 
water in staked enclosures ; after a few days the skin and flesh rot 
off, and can then be beaten out ; the skeletons are hung up'! in 
strings to dry and bleach in the air and sun. 
