120 



end view broadly elliptic. Diameter at widest part, 28 fi, 



thickness, 16 — 18 |U. 



This interesting new species from a pond at Brown's 

 Mills, New Jersey, was found late in September last. No 

 gehitinous sheath was observable. 



E. urn ae for me, n. sp. 



Semicells urn-shaped, tliree-lobed; terminal lobe dilated, 

 centrally sinuate; lateral lobes horizontal with sides ccmver- 

 ging, sinuate; Lasal portion protruding, emarginate; upper 

 part broadly rounded; a rounded sinus between it and the 

 end lobe; protuberances, one at each angle of the terminal 

 lobe, one at each of the basal angles, two intermediatt* and 

 one between the end and the lateral lobes. Diameter 55- G^^Nf. 



Wood Lake, Passaic Co., N. J. 



E. com pactum, n. sp. 



Very small, suborbicular, slightly longer than broad; 

 scmicells broad, transversely oval; apex a slight protulus- 

 rance with a linear incision j two small prominences, one ou 

 each side below the apical protuberance. Diameter 20 — 22 /«, 

 Length 22 ft, 



E. obtusu m, n, sp. 



Minute, twice as long as wide; semicclls obovate; huso 

 flattened, sides roundly diverging; end broadly rouiulcMl, 

 with a linear central incision. Diameter 14 /t, Length 25 /'. 



Ponds, Pennsylvania. 



Micrasterias Nordstetiana, n. sp. 

 • Of equal length and breadth ; scmicells three-hd^i'd ; 

 the lateral lobes divided hito two subcylindrical segnuMils 

 with a wide notch between, ends obtuse smooth, or j)ro- 

 vided with three or four small teeth, polar lobe exserted, 

 neck long, with a short, conical prominence about the middle 

 of each side; the ends broad, sinuate, with two horizontal 

 arms on each side, one of which is long and the other short, 

 both in the same direction, slightly diverging. 



Longwood Pond, Passaic Co., New Jersey. 



C. pseud obroomii, n, sp. 



This species is separated from C. Broome i, Thw., by 

 the total absence of a central inflation. 



Frequent in ponds, Sussex Co., N. J. 



In a small vial of specimens gathered by Mr. E. Pot Is, 

 of Philadelphia, while exploring Harvey Lake, Luzerne 

 County , for freshwater sponges , I found the same new 

 Micrasterias Nordstetiana mentioned above and one 



4 



new iStaurastrum, which I have named: 



S. Pottsii, n. sp. 

 Small, smooth; semicella in front view broadly elliptic^ 



