— 22 — 



minimum of the other while the averages are ten grooves apart. 

 It is in the joints of the stem, however, that the greatest differ- 

 ence to the eye is apparent. The new species has longer joints 

 than any other species I have seen, in some cases measuring six 

 and one-half inches. The shortest joint in 55 specimens measured 

 was 2>Ya inches long, while the longest of 81 hyemale reached 

 only 3% inches and the averages show a difference of nearly two 

 inches. 



The slender stems with a paucity of grooves and extremely 

 long joints are sufficient to make this a remarkable plant; but 

 there are other differences. The black markings on the sheath 

 encircle the stem obliquely, the sheaths themselves are thin and 

 chalky-white, the color of the stems is light gray green, and there 

 is a very noticable tendency in the stems to break at the joints; 

 the weight of the stem is sufficient to break it if held horizontally 

 by the basal joints. The stems when fresh are nearly smooth and 

 resemble B. hyemale intermedium in this respect, but the sheaths 

 are not dilated upward as in that form, nor are they colored like 

 the stem. I have .examined every sheet of Bquisetum in the Mis- 

 souri Botanical Garden without finding anything that by any 

 stretch of imagination can match it nor was a search through Mr. 

 Eaton's distributed specimens more successful. I therefore would 

 name and describe it as follows : 



Equisetum Ferrissi n. sp. Rootstock slender, resembling 

 that of B. hyemale; stems smoothish when fresh, 24 to 36 

 inches high, average about 26, slender, 3 to 5 thirty-seconds of 

 an inch in diameter, average 4 thirty-seconds; joints very long, 

 from 3^ to 6 l / 2 inches, average 4^, with from 12 to 22 grooves, 

 average 16; sheaths chalky- white, appressed to the stem, with a~ 

 black band encircling the base obliquely, widest on shortest side 

 of sheath, narrowest part of the band about one-fifth the length of 

 the sheath ; teeth cohering in groups, slender, deciduous, two- 

 thirds the length of the sheath, with a narrow brown central por- 

 tion and a wider hyaline margin ; leaves ridged below, grooved 

 at the tip, the tips dark brown, slightly thickened and incurved ; 

 grooves between the leaves extending below the basal band. 

 Fruiting parts not seen. 



Collected on the margin of a thinly wooded slope at Joliet, 

 111., Sept. 8, 1903, and described from specimens in my own 



