Genus Kiquisetum in the Yorkshire Coal-measures. 139 
The specimen described by these authors is a portion of a 
stem about 4 inches long and about 14 inch wide at the 
broadest part. It shows portions of thirteen nodes bearing 
the characteristic toothed sheath of Hgudsetum. The chan - 
nelling on the stem is feebly shown, but each rib ends in a 
tooth. 
The specimens I now describe, and one of which is here 
figured, show the fructification of an Equisetum. ‘They 
were collected by Mr. W. Hemingway, by whom they were 
communicated to me. 
The first example of the fossil was received a couple of 
years ago, but the earlier specimens discovered were not well 
preserved and their true nature was not discerned. More 
recently I have received some fine specimens from Mr. 
Hemingway, which reveal the true character of the fossil, 
The cones are about 1 inch long anda short distance above 
the base measure ;'5 inch across. ‘They are rounded at the 
base and have been attached to a thick stem, whose width , 
can be ascertained by the concave fracture where the cone 
has separated from the stem. ‘This “scar”? shows that the 
top of the stem must have had a thickness of 3%) of an inch. 
From about a third above its base the cone gradually narrows 
upwards, and ends in a blunt apex about 74) of an inch wide. 
The whole surface of the cone is covered with hexagonal 
plates whose diameter is from 7% to #5 of an inch. In the 
cenire of these smooth plates is usually a slightly prominent 
point. There appear to be nine transverse rows of plates in 
the cone figured (woodcut fig. a). 
On some of the other specimens the plates of the cone show 
three, seldom four, ridges running from the central point of 
the plate to the margin. ‘These I believe to be due to 
shrinkage of the specimen before mineralization, and they do 
not occur on the specimen figured, which is the finest 
example I have seen. 
For comparison I place beside the drawing of the fossil a 
figure of an immature cone of Hguisetum limosum, Sm. (from 
which the sheath at the base has been removed), taken from 
a photograph of a herbarium specimen that has been com- 
pressed during drying. ‘There is seen here in several of the 
plates the small central elevation, similar to what has been 
pointed out as occurring in the fossil (woodcut fig. c). Fig. d 
shows one of the peltate-shields of Hyudsetum limosum en- 
larged. Owing to the shrinkage of the cone in drying its 
hexagonal form is not so distinct as in the fresh state, but 
it exhibits the central point and the slight elevation of the 
margin of the peltate-shield. Fig. 6 gives one of the plates of 
