206 PROCEEDINGS OF THE ACADEMY OF [1887. 



film of the above S. bdhmii, ample for comparison with the next 

 species, S. novce terrce, which, in one point, it most curiously resem- 

 bles. Havin.^ giyen above the very clear description by Dr. M. 

 Hilgendorf, it is needful only to explain that while such a "layer of 

 parenchyma" around the gemmule as that seen in its associate spe- 

 cies, S. nitens, is absent, the gemmule of iS. bdhmii is provided with 

 a thick "granular crust" beneath which the gemmule spicules are 

 embedded, a capsule of skeleton spicules enveloping the whole. 

 The dermal or tlesh spicules, as he describes them, are niinute biro- 

 tulates, nearly resembling those of S. novce terrce and Meyenia everetti, 

 but somewhat larger than either: the shafts are more frequently 

 bent and a bolder enlargement at each extremity gives origin to more 

 widely spreading hooked rays. I incline to the opinion that the oc- 

 casional inflations of the shafts of these spicules as well as of the 

 spicules of the gemmule, indicate a want of full matui-ity in the spec- 

 imen when gathered. 



My interest in the description given of this little species by Dr. 

 Hilgendorf was such as to induce me to ask, through Mr. Carter, the 

 opportunity of making a personal examination of it; more partic- 

 ularly, to discover whether in it, as in S. novce terrce, the birotulate 

 dermal wa.s associated with a gemmule acerate showing any tendency 

 toward a birotulate form. This I find is no more the case than in 

 several other species oi'Sponc/Ula ; >S'. frciffilis for instance, where there 

 is also a grou})ing of recurved rays near the extremities. 



The curious fact that a coincidence of type has here associated the 

 Island of Newfoundland witli Central Africa, will not escape the 

 notice of any one ; nor that a corresjionding form in a neighboring 

 genus should only appear, as yet, in places so remote as a corner of 

 Massachusetts and the Ijakes of Nova Scotia. 



(17) Spongilla novae terrae, PoU.<. Piof. Acml. Nat. Sci. Pliila. ISSl. ]>. 22S ^^^.c. 



Sponge encrusting ; sarcode of the young growth, a dense mass of 

 minute spherical cells, embedding slender, curving lines of fascic- 

 ulated skeleton spicules, developing later into a very loose, open tis- 

 .^iie, with few connecting spicules. 



Gemmules rather luniierous, unusually large, spiierical; chitinoiLs 

 <'oatthin; crust apparently wanting. 



Skeleton spicules relatively few, slender, cylindrical, smooth or 

 sparsely microspined ; gradually pointed. (See cut.) 



Dermal or flesh spicules very abundant, minute birotulates of un- 

 equal size ; shafts slender, cylindrical, occasionally spined ; outer 



