472 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



Eqiiisetiim laevigatHm f. polystachyum A. A. Eaton, Fern Bull. 



11:44. 1903. 

 A form in which the stem and its branches (not due to an injury) 

 are simultaneously spike-bearing. 



Hippochaete Nelsoni (A. A. Eaton) comb. nov. 



Eqiiisetum variegatum var. Nelsoni A. A. Eaton, Fern. Bull. 12: 

 41. 1904. 



Intermediate between H. laevigata and H. hyemalis var. Jesiipi 

 but more like the latter in appearance than the former. The 

 rounded ridges and annual stems, however, place it more appro- 

 priately in the section Ambigua than in the Euhippochaete. The 

 parenchyma is frequently divided by the vallecular bast but not 

 regularly so. The sheaths in dried plants are liable to be slightly 

 ampliated. It has been collected in New York, Michigan, and 

 Illinois. 



