FEESH-WATEE SPONGES, 91 



4. — Spongilla Terr^-Nov^. 



1886. Spongilla Terrœ-Novœ, Potts (Proc. Acad. Nat. Sci., Pliila., 1881, p. 228). 



1887. " " MaoKay. 



Sponge greeuish, encrusting, thin, traA'crsecl by filaments of fascicled spicules forming 

 a loose tissue with lew connecting spicules. Skeleton spicules, slender, cylindrical, 

 generally smoothish, gradually pointed, about 0.00G7 inch long. Dermal or fiesh spicules, 

 minute birotiilates of varying size, about 0.0007 inch in length, and very al)undaut 

 Statoblasts globular, large, about 0.037 inch in diameter, having no crust enveloping the 

 chitiuous capsules. This capsule is covered with a layer of spicules which are robust, 

 fusiform, variable, but averaging 0.0015 inch in length, with from one to twelve strong 

 spines irregularly projecting from them, so that eaih has a different configuration of 

 spinous processes. 



Habitat. — Lakelets near Heart's Content, Trinity Bay, Newfoundland. — MacKay. 



[Note. — Dr. A. "Wierzejski found near Lemberg, in Clalicia (Verk. K. K. Zool.-Bot. 

 G-esell, 1888, pp. 529-36), a form of sponge which he thinks resembles this species. He 

 aro'ues that both forms are probably deformed varieties of Mei/enia M/illeri, Lieberkiihn. 

 The statoblast spicules of S. Terrœ-Novœ can easily be imagined in many particular 

 instances to be more like deformed birotules than like the more extreme forms of those of 

 S. MacKayi. And Mr. E. Potts has shown (Proc. Acad. Nat. Sci. Phila., 1887, p. 222) that 

 the birotulates of Meyenia fliaiiatilis var. uciiminaia, Potts, have the rotules deformed and 

 the axes produced beyond them ; and as the crust usually surrounding the chitinous 

 capsule is absent, they are compelled to assume the tangential position of Spongillas 

 instead of the radial position of Meyeuias. But on the other hand, the statoblast spicules 

 of S. lactislris, when the crust is very thick, may in some instances assume nearly a radial 

 position ; and the spines are stronger towards the two ends, so that we can easily think 

 of them as deformed, long-shafted, birotulates of the Meyenia type. But we might as 

 well call all the Meyenias by their original name Spongilla, and a great deal better, 

 than call the original Spongilla lacustris by the name Meyenia. No doubt a close phylo- 

 genetic relationship exists between the genera, but the degree of this relationship cannot 

 probably be guaged accurately by the variability of a single element in the species in 

 c[uestion. General morphology is the safer criterion. Now, the dermal spicules would 

 indicate a close relationship to M. Everetti, as would also the unusually large-sized 

 statoblasts and the filamentous structures of fascicled, skeleton spicules ; only the stato- 

 blast spicules have no close resemblance in this case. But S. Terrœ-Novœ has rather the 

 general appearance of S. MacKayi, the statoblast spicules are tangential as in the whole 

 geniis generally, and it has dermal spicules as has its congener, S. lacustris. On the 

 whole it appears to the author to have much more of the complexion of Spongilla than 

 of Meyenia, and especially more so than of M. MnUeri (Spongilla Mulleri, Lieberkiihn).] 



