C. INCERTAE SEDIS. _Fossils in Boghead ‘Coal’ referred by some authors to the Chlorophyceae._ During the last few years much has been written by two French authors, Dr Renault and Prof. Bertrand, on the subject of the so-called Boghead of France, Scotland, and other countries. They hold the view that the formation of the extensive beds of this carbonaceous material was due to the accumulation and preservation of enormous numbers of minute algae which lived in Permo-Carboniferous lakes. In an article contributed to _Science-Progress_ in 1895 I ventured to express doubts as to the correctness of the conclusions of MM. Renault and Bertrand[339]. Since then Prof. Bertrand has very kindly demonstrated to me many of his microscopic preparations of various Bogheads, and I am indebted to Prof. Bayley Balfour of Edinburgh for an opportunity of examining a series of sections of the Scotch Boghead. The examination of these specimens has convinced me of the difficulties of the problems which many investigators have tried to solve, but it has by no means led me to entirely adopt the views expressed by MM. Bertrand and Renault. [Sidenote: BOGHEAD.] The Boghead or Torbanite of Scotland was rendered famous by a protracted lawsuit tried in Edinburgh from July 29th to August 4th, 1853. A lease had been granted by Mr and Mrs Gillespie, of Torbanehill, in Fifeshire, to Messrs James Russell and Son, coal-masters of Falkirk, of “the whole _coal_, ironstone, iron-ore, limestone, and fire-clay (but not to comprehend copper, or any other minerals whatsoever, except those specified) with lands of Torbanehill[340].” After the Boghead had been worked for two years the Gillespies challenged the right of Messrs Russell, and argued that the valuable _mineral_ Torbanite was not included among the substances named in the agreement. The defendants maintained that it was a _coal_, known as gas-, cannel- or parrot-coal. A verdict was given for the defendants. Some of the scientific experts who gave evidence at the trial considered that the Boghead afforded indications of organic structure, while others regarded it as essentially mineral in origin. The Torbanite or Boghead is a close-grained brown rock, of peculiar toughness and having a subconchoidal fracture. It contains about 65% carbon, with some hydrogen, oxygen, sulphur, and mineral substances. A thin section examined under the microscope presents the appearance of a dark and amorphous matrix, containing numerous oval, spherical and irregularly shaped bright orange-yellow patches. Fig. 36, 1 shows the manner of occurrence of the yellow bodies in a piece of Scotch Boghead, as seen in a slightly magnified horizontal section. Under a higher power the light patches in the figure reveal traces of a faint radial striation, which in some cases suggests the occurrence of a number of oval or polygonal cells.