Maeyland Gteological Survey 40T 



certain localities of this age. The specimen represented in fig. 5 is 

 especially suggestive of such a relationship. 



Occurrence. — Patapsco Formation. Vinegar ilill, Maryland 



Collection. — U. S. National Museum. 



Abietites longifolius (Fontaine), Berry 

 Plate LXVII, Fig. 7 



Leptostroius longifoUus Fontaine, 1890, Mon. U. S. Geol. Survey, vol. xv, 



1889, p. 228, pi. ci, figs. 2, 3; pi. cii, figs. 1-4; pi. ciii, figs. 6-12; pi. civ, 



fig. 6. 

 Leptostroius longifoUus Fontaine, 1899, in Ward, 19th Ann. Rept. XJ. S. 



Geol. Survey, pt. ii, p. 671, pi. clxiii, fig. 15; pi. clxv, fig. 3. 

 Leptostrolius longifoUus Fontaine, 1906, in Ward, Mon. U. S. Geol. Survey, 



vol. xlviii, 1905, pp. 281, 481, 482, 491, 506, 528, 551, 557, pi. ex, fig. 11; 



pi. cxvi, fig. 1. 

 AMetites longifoUus Berry, 1911, Proc. U. S. Natl. Mus., vol. xl, p. 315. 



Description. — Leaves long and narrow, needle-like, 10 to 15 cm. in 

 length, aggregated in bundles. Bundles apparently borne on short shoots 

 with many leaves in each bundle. ISTo satisfactory venation can be made 

 out. Fontaine describes a various number of veins in these forms but 

 as nearly as can be determined these are simply folds due to compres- 

 sion or the angles of the leaf. 



This species has a considerable geologic as well as geographic range 

 having been recorded from the Kootanie formation of British Columbia 

 and the Fuson formation of the Black Hills. In the Potomac Group 

 it is of frequent occurrence and individually common being found in the 

 oldest as well as the youngest beds. The remains are always poorly 

 preserved and were evidently much macerated before fossilization; They 

 are closely comparable with Pinites Solmsi Seward of the Wealden and 

 with Pinus Peterseni Heer from the Kome beds of Greenland. 



They may also be compared with the genus Prepinus proposed by 

 Professor Jeffrey for certain structural material from the Upper Creta- 

 ceous. The type species of the latter genus came from the Earitan forma- 

 tion of Staten Island, Kew York, and is described as showing centripetal 

 xylem, although this feature is not clear in the figures of this species or 



