52 



HARDWICKE'S SCIENCE-GOSSIP. 



form and exquisite beauty of the individual bonelets 

 or ossicles which compose its calcareous skeleton. 

 It is quite beyond my power to describe them, but 

 I may say that in variety of outline and sculpture 

 they surpass the ossicles of any other species I know. 

 There is a lightness and elegance about them which 

 is wanting in almost all the others. The method of 

 obtaining these, detached and clean, is simple in the 

 extreme. Put one or more of the starfish into a 

 test-tube (mutilated specimens unfit for mounting will 

 do just as well), pour in some liquor potasste, boil 

 for a few minutes, wash in pure water, et voild tout. 



It will be seen from these few remarks that a series 

 of slides illustrating the structure of an Ophiocoma 

 may be mounted with very little trouble, and by 

 consulting a few books when leisure permits, much 

 valuable knowledge will be acquired ; and when 



Fig. 37. — Oj'kiocoma 7icglecia. (Natural size, and enlarged.) 



your neighbour drops in one evening and says, "My 

 boys are going to set up an aquarium, and they want 

 me to bring them some brittle stars from Brighton ; 

 I never saw one that I know of: what are they like ':;" 

 you can adjust your microscope, screw on the two- 

 inch objective, take out half-a-dozen slides, and 

 entertain him for ten minutes with a simple, agree- 

 able, free-and-easy lecture on the subject ; and, who 

 knows? perhaps some day his "boys" may return 

 your kindness by giving you an account of the 

 singular metamorphoses which Ophiocoma neglecta 

 undergoes before acquiring the bony framework 

 which you have mounted, and in other ways helping 

 you to solve some of the great problems of life in the 

 mighty ocean, 



"Where things that own not man's dominion dwell." 

 Penzance. E. D, Marquand. 



THE FOSSIL FLORA OF THE HALIFAX 

 HARD-BED COAL. 



No. L 



I 



By James Spencer. 



PROPOSE to bring before the readers of 

 Science-Gossip a series of short articles on 

 the above subject, which will be illustrated by 

 original sketches of fossil plants from my own 

 cabinet, and which are the result of my own labours 

 in this most interesting repository of fossil plants. 

 My object will be to endeavour to give short popular 

 descriptions of the fossil plants, and thus to aid in 

 spreading the knowledge of these beautiful fossils 

 over a wider area than they have hitherto been 

 known. 



Before proceeding with the description of the coal- 

 plants, it will be advisable to give a brief account of 

 the geological surroundings of the Halifax hard-bed 

 coal. The series of strata in which it occurs lie 

 between the rough rock (the uppermost member of 

 the millstone grit series) and the Elland flagrock. 

 The average thickness of this series in the neighbour- 

 hood of Halifax is a little over 500 feet. Two work- 

 able coal beds occur in it, namely, the hard bed, 

 the subject of this paper, and the soft bed, the 

 former being 2 feet 3 inches, and the latter i foot 

 4 inches in thickness ; besides these there are five or 

 six others which are too thin to be [worked for the 

 coal alone, but most of them are worked in various 

 places in conjunction with the fire-clay or seat 

 earth underlying them. Indeed the seat earth forms 

 in this neighbourhood a much m.ore valuable com- 

 modity than the coals, and is largely worked for the 

 manufacture of fire bricks, which are extensively 

 used in the construction of gas retorts, and furnaces, 

 &c., and in conjunction with the clayey shales of the 

 series, it is used in the manufacture of all kinds of 

 bricks for building purposes, sanitary tubes, chimney- 

 pots, &c. 



The coal beds in the neighbourhood of Halifax 

 have been worked from time immemorial. There 

 are deeds extant which prove them to have been 

 used for upwards of three hundred years, and very 

 probably they were worked at a much earlier date. 

 These strata are known all around the outcroji of 

 the Yorkshire coal-field, as the Halifax beds, which 

 seems to indicate that these coal beds were first 

 worked in the neighbourhood of Halifax, and that 

 the workings gradually extended on either hand 

 from Halifax. 



The section of Beacon Hill on the east of Halifax, 

 will give a good idea of the succession of the dif- 

 ferent beds composing this group. Crowning the 

 hill we have the valuable sandstone rock known as 

 the flagstone rock, which is so extensively quarried 

 all around the outcrop of the coal-field from Leeds 

 by Bradford, to Halifax and thence to Elland, Hud- 

 dersfield and Penistone. It is termed by the geo- 



