1880.] NATURAL SCIENCES OF PHILADELPHIA. 357 



On a former occasion he had described three species of Sp07ig- 

 illa from a small stream near Philadelphia, one of which, then 

 named S. tentaaperma, but which he now preferred to call S. 

 tenosperma, exhibited features so exceptional as almost to claim 

 for it generic distinction. 



He had since found the S. frag His of Leidy plentifuU}' in the 

 Schuylkill river below the dam, ( Leidy 's original localit}'), and 

 above the dam a lacustrine form differing from that before alluded 

 to. A very slender green species creeping along stems of sphag- 

 num, etc., had been received from a swamp near Absecom, N. J. 

 As it appeared to be entirelj' withoiit spined spicule of either 

 class, he proposed for it the name S. aspinosa. 



From the Adirondack lakes a beautiful species, believed to be 

 identical with S. stag)ialis, Dawson, had been received through 

 the kindness of Prof. H. Allen. Another lacustrine form which 

 yet is not ([uite S. lacustris, was brought from the lake near Cats- 

 kill Mountain House by Professors Cope and Hunt. Its status 

 has not been fully determined. 



From the cellar of an okl ruin at Lehigh Gap, Pennsylvania, he 

 had obtained four species, all of which appeared to be new. These 

 were all thin, creeping or encrusting sponges, three of them of 

 the birotulate tj'pe, briefly described as follows : 



S, argyrosperma — seed body or sphreruhv, large, silver-white, 

 densel}^ covered with radial spicule, the shafts of which are long, 

 stout, with numerous long spines, straight or curved ; the rotulae 

 at each end being replaced by 1-4 strong recurved hooks. 



S. repens — found creeping over the stems and leaves of Pota- 

 mogeton ; sphjerula^ also closely covered with spicuLne, shorter and 

 more slender than those of the preceding species ; their shafts 

 nearly smooth, the ra3^s of the rotulfe, six, eight or more, uniformly 

 incurved like the ribs of an umbrella. 



S. astrosperma — the sphairuhv haA'e the appearance of being much 

 smaller than in either of the former species, which is probably due 

 to the fact that the birotulate spicule surrounding the real cap^ 

 sules are very short ; the length of the shaft being less than the 

 diameter of the rays. Thej' are rather sparsely scattered over 

 the surface of the nearl}' transparent sphere, suggesting the name 

 star-seeded. 



The remaining form is considered a variety of 8. fragilis, and 

 called minuta ; sph.erula' much smaller than in the type species, 

 the dermal and superincumbent spicule terminated by sharp points, 

 while in the other they are universally truncate or rounded. 



A more particular description with measurements, etc., is in- 

 tended. 



Mr. Ezra T. Cresson was elected a member of Council, to fill 

 the vacancy caused by the resignation of Mr. Geo. Vaux. 



