20 The Ohio Naturalist. [Vol. XIII, No. 1, 



Several years ago, while visiting the New York Bot. Garden, 

 the late Dr. Underwood showed the writer specimens of E. laevig- 

 atum A. Br. from Engelmann's collections made at St. Louis in 

 August, 1843. These plants also had the rigid points on the 

 cones. They are probably from the same material from which 

 Braun received his specimens. 



Specimens of E. hyemale intermedium in the National Herba- 

 rium at Washington and at the Missouri Bot. Garden, including 

 cotypes named by Eaton himself, agree closely with Englemann's 

 specimens of E. laevigatum. Some of the specimens renamed by 

 Eaton were originally labeled E. laevigatum. One of Eaton's 

 cotypes of E. hyemale intermedium at the Mo. Bot. Garden 

 appears to the writer to be the same in all essential respects as 

 Engelmann's laevigatum material. The specimens was originally 

 labeled E. laevigatum. 



There can be no mistake as to the meaning of Braun's original 

 description of E. laevigatiim as translated by Engelmann and 

 printed in The American Journal of Science and Artsj. 



The species is characterized as follows : 



"Equiseta stichopora (winter-Equiseta). Stomata disposed in 

 two distinct ranges on each side of the groove ; each range formed 

 by one or more rows of stomata (All known species in this division 

 have hardy evergreen stems). 



Homophyadica. 



Ranges of stomata consisting each of one row. 



7. E. laevigatum A. Braun. 



"Stems tall, ^rect, simple or somewhat branching; carinae 

 convex, obtuse, .smooth; grooves shallow on each side; with a single 

 series of stomata, vallecular air cavities small, the carinal ones 

 very minute; central cavity large; sheaths elongated, adpressed, 

 with a black limb, consisting of about twenty-two leaves with one 

 carina at base and (by the elevation of the margin and depressions 

 of the middle) two towards the point; points linear— subulate, 

 sphacelate, caducous, leaving a truncate-dentate margin to the 

 sheath; branches somewhat rough; sheaths with about eight 

 indistinctly 3-carinate leaves; points persistent subulate, sphace- 

 late with a narrow membranous margin. 



Hab. On poor clayey soil with Andropogon and other coarse 

 grasses at the foot of the rocky Mississippi hills, on the banks of 

 the river below St. Louis. 



fBRAUX, Alexander. A monography of the North American species of 

 the genus Ecjuisetum; translated from the author's manuscript, and with 

 some additions, by George Engelmann. Am. Jour. Sci. and Arts 46:81-9L 

 (April, 1844.) 



