10 Ward — Species of Cycadco idea from Maryland. 



meters in longer and 12 to 26 centimeters in shorter diameter, with a girth 

 of from 70 centimeters to one meter; organs constitnting tiie armor ]iro- 

 ceeding at a riglit angle to the axis except above, where tliej^ are ascending, 

 and near the base, where they are sometimes slightly descending ; leaf 

 scars arranged in two series of spiral rows crossing each other usually at 

 a different angle to the axis of the trunk, the angle var3'ing from 30° to 

 75°; scars usually sul)rlioml)ic, /. ('. , with the lateral angles nearly equal 

 and the vertical ones unequal, the lower more acute than the upper, the 

 latter often reduced to a mere groove or wanting entirely and the two 

 upper sides together forming an arch, the whole scar simulating a drawn 

 bow and bowstring, but sometimes triangular, the upper sides joined along 

 a horizontal line, or more irregular in shajje, occasionally with four curved 

 sides and four acute angles; the width as represented by a line joining 

 the two lateral angles varying from 15 to 25 millimeters, and the height 

 as rei^resented by a line joining the two vertical angles (which would 

 rarely be parallel to the axis of the trunk) varying from (S to 15 milli- 

 meters; j-emains of the petioles usually present in the scars at differ- 

 ent distances from the summit, often bearing evidence of having been 

 disarticulated at a natural joint, sometimes indicating the existence of 

 two sucii joints at different depths in the scars, and showing that these 

 joints consist of a diaphragm across the petiole which may remain after 

 the substance of the petiole has jiartly decayed lielow it leaving a hollow 

 space, portions of the outermost diaphragms also sometimes adhering 

 to the sides of the scars in the form of a ridge surrounding them ; vascular 

 bundles rarely visible under an ordinary lens, but occasionally seen in 

 the form of a row near the outer margin all round the leaf base with a 

 few near the center; i-amentum walls usually rather thick, but vary- 

 ing from less than I millimeter to 9 millimeters, ordinarily with a more 

 or less distinct line marking the junction of tiie parts belonging to ad- 

 jacent petioles (commissure), sometimes with a distinct plate or layer of 

 less compact tissue between these, occasionally but rarely affected with 

 pits or small bi-act scars especially in the angles; reproductive organs 

 usually abundant, often solid and protruding, generally more or less dis- 

 tinctly marked in the center by the remains of the essential organs and 

 surrounded by bract scars in several concentric rows, but often decayed 

 in various degi'ees, leaving corresponding funnel-shaped cavities, com- 

 monly elliptical in cross-section, wider than high, very variable in size, 

 the major axis 15 to 40 millimeters and the minor 10 to 30 millimeters; 

 armor thin, 2 to 5 centimeters, usually joined to the internal parts by a 

 clear line, but without measurable thickness, but sometimes very irregu- 

 larly so joined and occasionally showing a thin libro-caml)ium layer; 

 woody zone 3 to 10 centimeters thick, usually with two or three more or 

 less distinct rings, the outer or parenchymatous zone thicker and firmer 

 than the inner or fibrovascular zone ; medulla usually homogeneous in 

 structure, elliptical, the major axis 8 to 17 centimeters, the minor 3 to 9 

 centimeters. 



Eighteen specimens are referred to this species. The type specimens 

 are of course the originals of T3'son, of which the one i)hotographed by 



