FROM THE SECONDARY ROCKS OF BRITAIN. 609 



From the Wealden beds at Brook Point, Isle of Wight. [British and Oxford Museums.] 



I have examined three complete trunks of this species, and several fragments of other 

 specimens. The longest specimen is the one in the Oxford Museum, which is 1<) inel 



c ic- 



long. The smallest of the three trunks is very perfect; it is 7 inches hi-rh, its long dia- 

 meter is 9 inches, and its short diameter 6£ inches; 3 inches of this la t measurement 

 consists of the permanent bases of the petioles, f inch of the cortical cellular layer, } inch 

 of wood, and 2 £ inches of medulla. The vascular bundle of each leaf rises upwards 

 through the outer cellular tissue, passing the base of three or four leaves before it passes 



outwards to its own leaf. The leaf springs from the stem opposite to, though considerably 

 above, the place where the vascular bundle left the woody cylinder. In a transverse ©- 

 tion of this trunk, two or three series of vascular bundles are seen in the cortical layer. 

 The petioles are separated from each other by a considerable layer of chaffy sea! -. which 

 densely clothed their bases. 



Corda, in his 'Beitrage zur Flora der Vorwelt' (tab. 17, p. 38), figures and describe! 

 the fragment of a fossil Cycad which he supposes came from England, and to which he 

 gives the name of Zamites JBucklandi. It consists of a small portion of a stem from tin 

 woody axis to the surface, like rolled and broken fragments of both the Isle of Wighl 



species which have been found on the shore at Brook. There are no indications, in the 

 complete and evidently accurate drawings, of any secondary axes ; but the form of the 

 petiole, the arrangement of the vascular bundles, and the abundant ramentum between 

 the petioles (which Corda considers to be intermediate or sterile scales), as well - tin 

 general form of the fragment, clearly show that it belongs to the genus Bmmettitet 

 Were it not that the petioles are in section so distinctly quadrangular and so small, I 

 should not hesitate to refer it to this species. It may, however, represent a distinct spe s. 

 with a smaller stem than the others; but this cannot be determined without additi nal 

 materials . 



Cycadites SchachtU, Coem., a stem from the remarkable deposit of coniferous remains 

 of Upper Cretaceous age, found at Hainault, in Belgium, probably belongs al to thii 

 genus. M. Coemans has not observed any axillary branches ; but bis admirable drau ,. 

 exhibits the large meshes in the woody cylinder characteristic of this group ol fossils. 



~ 



B. maximtjs, sp. nov. f • i 



Wk large, oval ; medulla large ; ™ody cylinder very thin and repeated* *«* c ° = ^"J 



layer large, everywhere penetrated by the ascending Innate vascular huata, 



are smaU and ve^nious; sections of ■*£H£££^2 



produced and very acute ; ramentum very abundant and separating 



of the leaves 



This species is ver Y near to B. Saxhyams', but it can easily be distinguished b, 



greater size, and by the very slender woody cyhnde 



r, . * nr~3t* nfiiseum of Practical Geology, Jem.) 



From the Lower Greensand at Shanklin, Isle of Wight. [Museum 



VOL. XXVI. 



5 F 



