MIryland Geological Survey 325 



four curved sides, often in the form of a cross, rarely subrhombic, small, 

 8 mm. to 12 mm, in vortical and 14 mm. to 25 mm. in lateral measure- 

 ment, averaging 10 mm. by 19 mm.; ramentum walls thick, 4 mm. to 

 10 mm., usually without commissure or punctations; leaf bases rarely 

 present when so, spongy or porous, without visible bundles; terminal 

 bud 6 cm. high, 65 mm. broad at the downwardly convex base, definitely 

 bounded below, symmetrically conical above, consisting of a mass of 

 densely matted bracts imbricated along a central axis; reproductive or- 

 gans few and imperfectly defined, usually cavitous in the centre and 

 sometimes surrounded by irregular-shaped bract scars; armor rather 

 thin, 2 cm. to 4 cm. ; liber and cambium obscure ; woody axis divided into 

 several rings, sometimes consisting of a loose, open structure separated 

 by thin, firm plates, the inner face next the medulla definitely marked 

 by the remains of vessels and medullary rays ; medulla large, marked on 

 the external surface by thin longitudinal ridges or lamellae varying from 

 1 cm. to 3 cm. in length, the ends overlapping adjacent ones (Cycadeo- 

 mydon Saporta), internal parts coarse and porous or somewhat cham- 

 bered. 



This species resembles Cycadeoidea McGeeana in the general form of 

 the trunks, but the external organs are very different, the most striking 

 distinction being the very thick walls. 



Cycadeoidea GoucHEniAisrA Ward 

 Plate XLVI 



Cycadeoidea GoucJieriana Ward, 1897, Proc. Biol. Soc, "Washingtoii, vol. xi, 



p. 14. 

 Cycadeoidea Goucheriana Ward, 1906, Mon. U. S. Geol. Surv., vol. xlvili, 



1905, p. 451, pi. Ixxxvii, fig. i, 3; pi. Ixxxix, fig. i, 3; pi. xcix. 



Description. — Trunks large, cylindrico-conieal with elliptical cross 

 section, 30 cm. to 50 cm. high, 25 cm. to 50 cm. in diameter, light colored 

 and of low specific gravity, somewhat chalky and friable; lower leaves 

 somewhat deflexed, upper ones ascending the line between the two definite 

 and encircling the trunk near the middle ; leaf scars arranged in two sets 

 of spiral rows, both having nearly the same angle to the axis, 45° or 



