EQUISETITES. 33 



3. Equisetites Yokoyamse, sp. nov. 



1846. ? Carpolithus sertum, Dunker, "Wealdenbildung, p. 22, pi. vii. fig. 3. 

 1875. Equisetites Burchardti (in part), Schenk, Palaeontographica, vol. xxiii. 

 p. 157, pi. xxvi. fig. 1. 



Type. Tubers and fragments of stems from Ecclesbourne, near 

 Hastings. British Museum. "Woodcuts, Figs. 2, 3 and 3*. 



Stem narrow, internodes about I'l cm. in length and 5 mm. 

 in breadth ; tubers narrowly elliptical, attached singly or in chains 

 to the nodes. 



In the National Collection there are several specimens of Equi- 

 setaceous tubers, both isolated and attached to stems, which are 

 distinct in shape from those of E. Burchardti, Schimp. Mr. Rufford 

 informs me that these two kinds of tubers never occur together, 

 the specimens of the latter species being found at Bexhill, those 

 of the other type at Ecclesbourne. I have decided, therefore, 

 to give expression to the distinctive character of the Ecclesbourne 

 tubers, and have named the new species after Dr. Yokoyama of 

 Tokyo, who has in recent years made valuable additions to our 

 knowledge of the Mesozoic floras of Japan. 



In E. Yokoyamce there are very few details of structure shown 

 in the sandstone specimens. The stems are usually in the form 

 of smooth slender casts with little or no indication of longitudinal 

 ribs and grooves, or leaf-sheaths ; the tubers differ from those of 

 E. Burchardti in their smaller size and narrower elliptical form. 



Fig 2 (V. 2871). Fig. 3 (V. 2871). Fig. 3* (V. 2335). 

 Tubers of Equisetites Yokoyama, sp. nov. 



One of the best examples is represented in Pig. 2 ; part of a 

 shrunken tuber is shown in place, and immediately below it is 

 a branch attached to the node. This example, with several others, 

 has probably been preserved in the sandy soil in its original 

 position of growth. 



