470 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



before winter has set in. It may be noted here that growth In 



the evergreen species begins, in Michigan, about the middle of 



May and continues through the summer. 



Keweenaw Peninsula, Mich., Fartvell jgg4}4< June 29, IQIS* 

 Algonac, ^lich.. Faru^ell 3640, 3684}/^, 3685, June 21, 1914. 

 Detroit, Mich., Farivell 2ioe, June 24, 1902. Rochester, Mich., 

 Farwell 210c, July 4, 1896; 3721 }4, July 19, 1914. Stony 

 Creek, Mich., Farwell 3438^2, June 8, 1913. Parkedale Farm, 

 Mich., Farwell 2701, June 11, 1912; J^773^, June 11, 1914; 

 3705, June 28, 1914. Common west of the Mississippi and in 

 the "Lake States." 



HiPPOCHAETE LAEVIGATA var. Eatonli var. nov. 



Eqiiisetum hiemale var. intermedium A. A. Eaton, Fern. Bull. 

 10: 120. 1902, as to the annual plant. 



Externally, this variety can be distinguished from the typical 

 species only by the roughness of the stem and the occasionally 

 apiculate spikes. The anatomy is very variable, sometimes that 

 of the species, sometimes that of H. prealta var. affinis; now inter- 

 mediate when the parenchyma is continuous, and now combining 

 both types when both the carinal and vallecular basts divide the 

 green parenchyma, splitting it into irregularly triangular blocks. 

 It may be found alone, associated with H. laevigata, H. prealta, 

 or its var. affinis, or with all of these. In the original description 

 of Equisetum hiemale var. intermedium, Eaton included annual 

 and evergreen plants with teeth that were caducous, deciduous, 

 and persistent. In the seventh edition of Gray's Manual he had 

 restricted the variety to the evergreen plant with caducous teeth. 

 This left the evergreen plant with broader sheaths and persistent 

 teeth and the annual plant with caducous teeth without names. 

 For the former I have adopted Engelmann's varietal name of 

 scabrella; to the latter I gi\e the \arietal name Eatonii. The 

 first stems of the season fruit in June and jxTish in July and 

 August when the later stems are fruiting and others just coming up. 

 At this time it simulates //. prealta var. intermedia but is quickly 

 and readily differentiated by its annual stems, which have not the 

 bright green of that variety. Some plants have completely 

 perished before winter sets in while others in greater or less degree 

 survive the winter but these parts have perished before the new 



