246 Systematic Paleontology 



Fragments from the ISTeocomian of Japan, showing oval sori, are referred 

 to this species by Yokoyama {loc. cit.). 



Occurrence. — Patuxent FoRMATiOiSr. Fredericksburg, Dutch Gap, 

 Alum Rock, Telegraph Station (Lorton), Potomac Eun, Virginia; N^ew 

 Eeservoir, Ivy City, District of Columbia; Broad Creek (?), Maryland. 

 Arundel Formation. Arlington, Hanover, Howard Brown Estate, 

 Maryland. Patapsco Formation. Brooke and vicinity. Chinkapin 

 Hollow, Virginia; Federal Hill (Baltimore), Vinegar Hill, Maryland. 



Collections. — U. S. National Museum, Johns Hopkins University, 

 Goucher College. 



Cladophlebis constricta Fontaine 

 Plate XXIX, Fig. 3 



CladophleMs constricta Fontaine, 1890, Mon. U. S. Geol. Surv., vol. xv, 1889, 



p. 68, pi. ii, fig. 11; pi. iii, fig. 2; pi. vi, figs. 5, 6, 8-14; pi. xxi, figs. 9, 



13; pi. clxix, fig. 2. 

 CladophleMs latifolia Fontaine, 1890, Mon. U. S. Geol. Surv., vol. xv, 1889, 



p. 69, pi. iii, fig. 1; pi. vi, fig. 4. 

 CladophleMs constricta Penhallow, 1905, Summ. Geol. Surv., Can., 1904, 



p. 9. 

 CladophleMs virginiensis Fontaine, 1906, in Ward, Mon. U. S. Geol. Surv., 



vol. xlviii, 1905, p. 512, pi. cxi, fig. 7. 

 CladophleMs constricta Fontaine, 1906, in Ward, IMd., vol. xlviii, 1905, pp. 



280, 297, 504, 528, 547, pi. Ixxi, fig. 26. 

 CladophleMs constricta Knowlton, 1907, Smith. Misc. Coll., vol. iv, pt. i, 



p. 109. 

 CladophleMs constricta Berry, 1911, Proc. U. S. Natl. Mus., vol. xli, p. 314. 



Description. — Frond large, bipinnate or tripinnate. Principal rachis 

 rather slender. Pinnae remote, shortening rapidly distad. Proximad 

 they are pinnatifid, changing first into pinnules with undulate margins 

 and then into those with entire margins in passing toward the apex of 

 the frond. Pinnules elliptical in outline, constricted at the base, which 

 is rounded or subauriculate. Venation of the usual Cladophlebis type. 



This species has been identified at a number of localities in Maryland 

 and Virginia, but it is not common at any of these. Outside this area 

 it has been reported from the Kootanie of Montana, and very similar 

 forms occur in the Kome beds of Greenland, as, for example, those which 



