JIKASSIC CYCADS FROM WYOMING. 18i> 



niilv n thin \nccv is iiiissintr between Xos. 500.136 and 100.210. If this 

 were present, we should liave nearly half of a small compressed trunk. 

 No. 500.470 joins Xo. 100. ;«S, and Xo. 500.504 joins Xo. 100.312. The-se 

 la.st four, with about a dozen other frajjments, undoubtedly represent the 

 type trunk, and ihe strui-ture indicates thai they lay veiy close to the 

 type Xo. 500.71 (see PI. cxxviii). Xo.s. 500.178 and 500.422 constitute 

 anothei' complementary couple of a somewhat different class, l)u1 evi- 

 dently l)elono;inji to this species. They show the internal structure 

 very clearly and also consitlerable of the surface, indicating a much 

 compressed trunk probal)ly larger than that to which the type speci- 

 mens belong. Xos. 100.258 and 100.275 also go together and represent 

 still another trunk not othei'wise represented. They all have the char- 

 acteristic internal structure and surface markings of the species. Xo. 

 100.245 is the lai'gest specimen, weighing 0.9 kg. It is a slab from 

 one side of a trunk, showing considerable of the surface and a broad, 

 smooth, tangential fracture. 



PI. LII, Fig. 2, is a side view of the triangular section i-esulting 

 fi'om joining Xos. 500.178 and 500.422, and PI. LII, Fig. 3, the internal 

 structure of the inner fracture of No. 500.422. PI. LII, Fig. 4, shows 

 one of the fractures of Xo. 500. 130, and PI. LIII the tangential fracture 



of No. 100.245. 



Cycadell-v ExodEXA Ward. 



PI. LIV. 



I'JOU. ('!/cii(hllii exogcna Ward: I'nic Wash. Acad. Sci., Vol. I, p. 27.3; Twentieth 

 Ann. Rep. V. S. Geol. Surv., 1898-99, Pt. II, p. 404, pi. exxx-cxxxvii. 



A limited munber of specimens, most of them fragments, are 

 referred to this species. By far the largest and most complete is No. 

 500.514, which weighs 2.04 kg., although the armor has disappeared 

 from more than half of it and a considerable part of the axis is also 

 wanting. This specimen is difficult to orient, as neither base nor sum- 

 mit is present and the direction of the axis is not clear, while the surface 

 is covered with ramentum, but one of the fractures which passes through 

 the entire woody zone and the armor was found to join one of the planes 

 of fi'actui-e of the small specimen Xo. 100.249, adding considerable to 

 the trunk. This .specimen weighs 0.45 kg., making the total weight 



