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HYALONEMA (HYALONEMA) AGASSIZI. 
establishment of separate varieties. The distinction of different forms within 
the species, designated A, B, C, D, E, and F, is a sufficient division. 
The species composed of these six forms is most closely allied to the Hya- 
lonema ( Hyalonema ) obtusum and the Hyalo7iema ( Hyalonema ) polycaulum. 
The outer appearance of the variety gracilis of H. ( H .) obtusum is indeed nearly 
the same as that of form A. These latter differ, however, from H. (H.) obtusum 
in the following respects : — the dermal pinules are considerably longer in both 
varieties of H. (H.) obtusum than in any of the forms described above; the 
