426 BULLETIN OF THE BUREAU OF FISHERIES. 
before, but that the supply from the latter source must at most have been small is 
shown by the fact that its total exports to all countries in the year mentioned were 
valued at but some $10,000. In any event, sponges other than those from the 
Mediterranean were but little known and the venturesome cargo from Key West 
narrowly escaped being thrown away as worthless. Its ultimate sale, however, 
established a market for this newly discovered product of the keys, and several 
merchants at Key West began to buy the better grades and to take them in trade. 
It is said that at first the price was but 10 cents per pound, presumably for 
sheepswool sponges, but as the quality of the domestic product became better 
known the price improved, there began to be a systematic investment of capital 
to take the place of the desultory fishery previously carried on; and a class of men 
developed whose principal or sole business and means of livelihood was gather- 
ing sponges. 
THE SPONGING GROUNDS. 
The sponging grounds as at present developed are broadly divided into two 
widely separated areas, the ‘‘Bay Grounds,” lying in the open waters of the Gulf 
of Mexico, from about Johns Pass to St. Marks, and the ‘‘Key Grounds,” 
stretching along and among the reefs and keys from Cape Florida to Boca 
Grande Key. 
That there is sponge-bearing bottom between the New Ground off Cape 
Sable and the mouth of Tampa Bay admits of little doubt, but notwithstanding 
that the Key West fleet has traversed that region year after year in going to and 
from the Bay grounds, practically no sponges have been taken there, owing 
mainly to the depth and almost constant turbidity of the water. A few spongers 
have reported seeing sponges, but never in considerable quantities. 
The grounds as exploited and worked by the hookers up to the time of the 
introduction of diving apparatus, in April, 1905, covered an area of 4,350 square 
miles, of which the Bay grounds contained about 3,400 and the Key grounds 
about 950 square miles. It must not be considered, however, that all of this 
area is productive, for on the contrary the actual sponge-producing bottom in 
any given field is far less than the barren areas with which it is mingled. 
Sponges grow neither on sand nor mud, nor primarily on grassy areas, but 
must have some firm clean body to which to attach when the small free-swimming 
larva is ready to settle down and assume its final fixed condition and form. 
Among the Keys the bottom in the main consists of sand and more or less cal- 
careous mud or marl, either naked or less frequently supporting a grassy growth, 
while on the Bay grounds it is generally sandy offshore with more or less grass in 
the shallow waters close toland. Inthe channels and other places among the keys 
where the currents run with sufficient velocity to scour the bottom or the waves 
prevent the excessive deposit of silt, the coral rock is exposed and furnishes 
