202 The Natural History of a Siberian Coal. 
sheath permeated as it seems by peroxide of iron. The author 
compares these threads with those of Cladotlirix dichotoma and 
names them Cladothricinium Pancratovi. 
In chapter III all organisms mentioned have a detailed 
description. To moulds referable to mucor-moulds, the author has 
given the name Mucorvelium palceomycoides, to the radiating mould 
Actinomycoidium floccidum and to the yeast organisms Mycogemma 
saccharotnycoides. The radiolarian is called Acanthosphcera parvula, 
the flagellate is described under the name Disoma piagellata. One 
of the rotatoria is referred to Rattulidae and described under the 
name Palceorattulus elegans , and the other belonging to the Brachio- 
vidtz is named Tlioracozoon hrachionoides (in the work Doracozoon 
bracliionoides is a misprint). The beetle of the Staphylinoidea group is 
named Microcantharis minutus. In chapter IV the author expounds 
the formation of the new coal by accumulation of fucoid sea-weeds 
(drifted by the tide and waves of the sea) on the sea-shore where 
they were converted into mucilage and covered by moulds, but not 
on the bottom of the sea as Moor had once supposed for all coals. 
In conclusion the author points out the important significance of 
this coal for the solution of geological problems, because the 
recognition of sea-weeds in Himanthaliopsis Sniatkovi makes it 
probable that the sediments of the coal-bearing series of Kuznetsk 
basin were deposited in a sea gulf but not in a continental lake as 
was formerly supposed. A tricoloured autotype in water colours 
from nature by Miss E. D. Kovalsky and phototype plates from 
micro-photographs made by the author accompany the work. 
