STAURASTUUM. 14& 



Var. PENTACLADUM, Wolle. Plate LIII, figs. 32-35. 



Separated from the other forms by the number of arms ; 

 they vary greatly in size, always symmetrically arranged 

 with five curved arms. 

 Diameter 44-85 /^. 



Have one or the other form from every State hitherto 

 explored. 



ST. PARADOXUM, Meyen. Plate LIII, figs. 36, 37. 



Cells rough with minute granules ; front view with elon- 

 gated diverging processes which are bifid or trifid at the 

 apices ; end view triangular or quadrangular. 

 Diameter 40-60 yu. 



Ponds, New York, Pennsylvania, New Jersey, Massachu- 

 setts. 



The figures represent an extraordinary form ; usually the 

 apices of the processes are more minutely trifid. 



Var. OSCEOLENSE, Wolle. Plate XL VII, figs. 8, 9. 



This variety differs from the typical form in its larger size, 

 quadrangular body and in the large trifid, hooked, apices of 

 the arms. 



Diameter of spread of arms 60-70 ^u. 

 Lake Osceola, Winter Park, Florida. 



ST. ARACHNE, Ealfs. Plate LIII, figs. 38-42. 



Semi-cells minutely granular, suborbicular, with elongated,, 

 slender, often incurved processes; end view with three to- 

 five linear rays ; apices obtuse. 

 Diameter 40-50 >w. 



Habitat same as that of the preceding. Distinguished 

 from it by its more slender arms and obtuse apices. 



ST. COMPTUM, Wolle. Plate LIII, figs. 43-46. 



Small, granulate; semi-cells subfusiform, ends convex; 

 arms more or less converging, separated by an elongated, 

 cylindrical, somewhat swollen isthmus, ribbed in the center;, 

 vertical view six radiate ; rays straight, tricuspidate at the 

 ends. 



Diameter 30-40 p. ; length 40-50 ju. 

 Not rare in ponds, New Jersey. 



ST. ELONGATUM, Barker. (St. terebram, Nord.) Plate LVII r 



figs. 11, 12. 



Elongate; semi-cells subtriangular; base globosely inflated, 

 produced into a cylindrical column inflated at the end, and 



