200 The Jurassic Plant Beds of Roseberry Topping. 
by the forking of the secondary veins very close to the midrib 
and the wide separation of the ultimate divisions. 
The plants which in their external form seem identical 
with Thinnfeldia rhomboidalis Ett., are probably the most 
interesting of the whole flora from several points of view. 
They occur in such abundance as to form beds nearly an 
inch in thickness, which consist almost entirely of plant 
remains with very little admixture of muddy material. The 
individual leaves and leaflets readily separate, and the deposit 
resembles the so-called ‘paper-coal’ of Russia. In the beds 
on the main escarpment, at a considerable distance away, 
this Thinnfeldia is the dominant plant throughout three or 
four feet of shale, and from this locality very beautiful speci- 
mens can be obtained. From the immense quantities of 
Thinnfeldia leaves seen in this district, it is evident that the 
plants which bore them must have dominated the vegetation 
in the neighbourhood at the close of the Liassic period, though 
their remains are very rare in other parts of Yorkshire. 
Many of the other plants in the black shale are very 
beautifully preserved in a mummified state, and can be readily 
detached from the matrix if the original cuticle was moderately 
thick. Specimens of Zamites, Anomozamites, Ctenozamites, 
Ctenis, etc., can all be obtained in this way, and from them 
good microscopic preparations, showing the structure of the 
epidermal cells and stomata, can be obtained by treatment with 
potassium chlorate and nitric acid.* 
Few traces of ‘ flowers’ or seeds have yet been obtained, 
though some large separate seedlike structures comparable 
with those of modern Cycads have been observed. Probably 
further investigation will lead to more discoveries in this 
direction. 
The Roseberry beds not only present a deposit of the 
greatest interest to the geologist and botanist, but they 
undoubtedly offer a large and promising field for investigation. 
They indicate also the probability of finding other rich plant 
beds of the same horizon on other parts of the escarpment in 
the district, which should lead to further extensions of our 
knowledge of the Jurassic Flora of Yorkshire. 
——— 
Good old Filey! According to the daily press a ‘six-legged field-mouse 
has been caught in a trap at Filey.’ 
Mr. E. Hawkesworth, of Sunny Bank, Crossgate, Leeds, has been elected 
Hon, Treasurer to the Yorkshire Naturalists’ ‘Union, in place of the late 
H. Culpin. 
The Senate of the Dublin University has agreed to the conferment of 
the honorary degree of Doctor of Science upon Professor A. C. Seward, 
F.R.S., a past-president of the Yorkshire Naturalists’ Union. 
ne 
* For the methods employed see New Phytologist, 1912, p. 1c9. 
Naturalist, 
