EUASTRUM. 113 



E. INSIGNE, Hass. Plate XXXI, figs. 39-43. 



Semi-cells longer than broad, inflated at the base, sides 

 entire, and tapering into a long slender neck ; end lobe di- 

 lated with linear notch ; end view quadrangular, with angles 

 slightly protruding, and a swelling on each of the shorter 

 sides ; end lobe cruciform as shown on the middle of fig. 43. 



Diameter 30-35 yw. 



Ehode Island, Massachusetts, Pennsylvania, New Jersey 

 and Florida. 



E. MAMMILI.OSTJM, WoUe. Plate XXX, figs. 14, 15. 



Cells in length twice the diameter ; semi-cells three lobed ; 

 basal lobes wide and nearly half as high as the semi- cell, 

 drawn out in the center into a narrow column one-third to 

 one-fourth the diameter of the body ; dilated at the end, 

 sinuate, four-parted ; base with six mammiform protuber- 

 ances ; membrane punctate ; end view oval with three di- 

 verging mammiform prominences at each end. 



Diameter of center of cell 68 yu. ; length 118 /i. 



Ponds, Mount Everett, Mass., and Sussex County, N.J. 



E. Hastingsii, WoUe. Plate XLII, figs. 16, 17. 



Cells small, a little more than one and one-half times as 

 long as broad ; semi-cells three lobed, lateral lobe horizontal, 

 deeply emarginate; terminal lobe a stout column rather 

 more than one-third diameter of the body and about the 

 same height, dilated at the end, apex ornamented by a row 

 of tubercles, giving it a crenulate appearance ; lateral view 

 similar except that the basal lobes are one-third or one- 

 fourth narrower ; transverse view broadly elliptic, with 

 three inflations on each side and one on each end ; end view 

 shows terminal lobe a crenulate circle of about a dozen 

 tubercles. 



Diameter 35-40 yu. 



Coll., W. N. Hastings, Cocheco River, New Hampshire. 



E. ATTENUATUM, Wolle. Plate XXX, fig. 17. 



Small, twice as long as wide ; semi-cells three lobed, basal 

 lobes broad, emarginate ; terminal lobe a column with nearly 

 parallel sides, apex truncate. 

 Diameter 35 yu. 



Bather rare, but I found a considerable number in swamp 

 pools, Bucks County, Pa., and near Ocean Beach, N. J. 



