EEPORT ON THE TETRACTINELLIDA. 
439 
arranged in two groups, radiating from opposite poles ; the centrum 0’055 mm, in 
diameter. 
Colour . — Eed. 
Habitat . — South coast of Lesina, two miles from the shore. 
Tethya diploderma, 0. Schmidt. 
Tethya diploderma, 0. Schmidt, Spong, Atlant. Gebiet., p. 52, pi. iv. fig. 11, 1870. 
Sponge . — As in Tethya lyncurium. 
Spicules. — I. Megasclere. 1 . Strongyloxea, sls in Tethya lyncurium. 
II. Microscleres. 2. Spheraster, actines short, 0’03 mm. in diameter. 3. Aster, 
actines six to nine in number, often curved, with occasional tubercles, terminally tylote, 
0*008 5 mm. in diameter. 
Habitat. — Antilles. 
Remarks. — The structure of the cortex, which Schmidt seems to think exceptional, 
appears to me precisely similar to that of small specimens of Tethya lyncurium, such as 
occur in the variety Tethya lyncurium, var. norvagica. 
Tethya {?) innocens, N., 0. Schmidt. 
This is mentioned by 0. Schmidt (Spong. Atlant. Gebiet., p. 51) as uniting genuine 
Suberite tylostyles with asters. 
Tethya repens, 0, Schmidt. 
Tethya repens, O. Schmidt, Spong. Atlant. Gebiet., p. 51, 1870. 
Sponge. — A long crust, 10 mm. thick in the middle, with numerous flat papillae, into 
which spicular bundles enter. 
Spicules. — I. Megascleres. 1. Strongyloxea, somewhat strongylate at the ecactinal 
end. 2. Strongyle, and 3. Tylotoxea, smaller than the strongyloxea. 
II. Microsclere. 4. Spheraster, like that of Tethya lyncurium, "with dichotomose 
actines. 
Habitat . — Florida. 
Remarks. — Although not mentioned by Schmidt, probably other asters besides the 
spheraster are present. The sponge may possibly be assignable to the genus Columnitis. 
