4§ SPONGES 
ongia. I know of asingle locality only where it uccurs, and here it grows in a 
very restricted area. This is a sandy bar which extends from the eastern end 
of Hog Island into the channel which divides this little island from a neighbor- 
ing key which lies to the eastward. That portion of this bar that is inhabited by 
these sponges is never exposed by the falling tide, so that the Verongias are 
always under water, although sometimes they come very near the surface. 
The Filamentous Sponge is always attached to a rock or coral, but these 
bases were surrounded by sand on the bar where I found them. ‘There were 
a few other species of sponges growing there, notably a dark purple species of 
Pandaros, a spiculigenous sponge, and a few cthers of this group, but although 
some of them were parasitic in habit, none grew on the Verongia, nor did I ever 
find Filamentous Sponge attached to other sponges. 
This bar, or rather that portion of it on which this species grew, was about 
a hundred yards long by fifty yards wide, and even here the sponge was not 
very common. I found about twenty-five specimens, and these were all I ever 
saw anywhere, although, according to Duch. et Mich., the species occurs about 
St. Thomas. 
They are beautiful objects when in their native element, especially the 
branching forms, as then the long yellow filaments wave gently in the flowing 
current, closely resembling the branches of some of the algae. When the sponge 
is living, the filaments have a tough, rubber-like consistency, and are then not 
easily broken: but when dried, they are exceedingly brittle. This former 
elasticity may be in a great measure restored to them, however, by placing the 
sponge in water. 
