412 
THE LAST DECADE. 
the structure of the latter and the fossil is given. Two species of Cal- 
amostachys are known, C. Binneyana, of Schimper, and C. Casheana, 
named by Professor Williamson after the author, and described in 
his 11th memoir on the organization of the fossil plants of the coal 
measures, from a specimen discovered in the Halifax beds by the late 
Captain Aitken. Illustrations are given of the features distinguishing 
the two species. The paper is supplemented by a bibliogTaphical 
list of works and authors who had previously dealt wdth the subject. 
In addition to the pal?eo-botanical papers already referred to, Mr. 
James Spencer read a paper on Astromyelon and its affinities. The 
genus w^as described by Professor Williamson in 1878. Since that 
time Mr. Spencer had discovered a number of other specimens which 
he described, and expressed his opinion that the genus occupied an 
intermediate position between the lepidodendroid plants and the 
gymnosperm dadoxylons . 
To Mr. George Robert Vine the Society is indebted for a series 
often papers treating of the microscopic organisms in the strata 
between the Wenlock Shales and the Greensand, but mainly describing 
those of the Carboniferous Rocks of Yorkshire. Mr. Vine is a recog- 
nized authority on the Pol5^zoa of these strata, and his papers are 
necessary for reference in any country where the Polyzoa are studied. 
In 1881 he contributed to the proceedings notes on the Car- 
boniferous Polyzoa of North Yorkshire. In it the author deals with, 
and partly describes, the Polyzoan fauna found in the shales of North 
Yorkshire, at Richmond and Hurst. Some years previously to the date 
of the paper, Mr. Vine received from Mr. John Harker, of Richmond, 
a packet of unw^ashed clay, from some locality in the neighbourhood of 
Hurst. The sample, after careful washing, was found to be rich in 
fragments of Polyzoa, Entoraostraca and Foraminifera. Twenty-two 
species of Polyzoa are either described or referred to, many of which 
differ from the forms so abundant in the Lower Limestone Shales of 
Scotland, but in all probability the whole may be referred to as 
belonging to the Upper Limestone Series of Scotland, more par- 
ticularly those found in Gair and Belstonburn (Yoredale ?). 
A second paper on the Carboniferous Entomostraca and Forami- 
nifera of North Yorkshire was read in 1883 ; the specimens were 
