IN THE STRATA OF THE CARBONIFEROUS SERIES. 39 



great breadth of the medullary rays, which are in some instances nearly 

 equal in diameter to the intervening series of cellules. 



Fig. 5. Is part of a longitudinal section parallel to the medullary rays. 

 The elongated cellules of the woody tissue are less regular than in the last 

 species. Their walls, however, are marked precisely in the same manner. 

 The great breadth and regularity of the medullary rays are especially re- 

 markable, and give the tissue, when viewed in this direction, a very peculiar 

 aspect, which is rendered more remarkable by the frequent appearance of 

 transverse dissepiments in the cellules of the woody fibre. 



Fig. 6. Represents part of a longitudinal section parallel to the bark. 

 The tissue is composed of elongated cellules, more or less waved, with trans- 

 verse dessepiments, continuous walls, and intervening medullary rays of 

 great breadth. I have counted as many as fifteen series of cellules in these 

 rays, and the lowest number seems to be eight, but as sections of this kind 

 may be more or less oblique, the number may sometimes seem more than it 

 really is. 



To this species I propose giving the name of Pitus primceva. 

 The genus is very closely allied to Pinites, and I should not be very 

 much disposed to censure those who might unite them, provided they kept 

 the Piti as a section. At the same time, it presents a very different appear- 

 ance from any species of that genus which I have examined. 



FOSSIL PLANTS FOUND AT ALLENBANK, IN BERWICKSHIRE. 



This locality is about seven miles from Lennel Braes, and is near the 

 junction of the Whitadder and Blackadder. It affords a considerable va- 

 riety of fossil vegetables : Sigillarias, Lepidodendra, and fronds of Ferns. 

 Among these also occur large masses of fossilized remains of vegetation, of 

 irregular forms, ge erally flattened, and seldom exceeding two or three feet 

 in length. These masses are invested with an irregular coat of carbona- 

 ceous and clayey matter, in which are inserted small fragments of stems, 

 shewing that it is not the true bark carbonized, but a confused assemblage 



