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HARDWICKE'S SCIENCE - GOSSIP. 



[Nov. 1, 1866. 



There is a small beetle, the name of which I can- 

 not give— I can only say that it is about a quarter of 

 an inch in length, has burnished brown elytra, and 

 five joints in the tarsus. The gizzard of this 

 beetle when opened is scarcely as broad as a fine 

 thread somewhat flattened ; on this narrow gizzard 

 there are three brown specks, one of which, when 

 greatly magnified, is found to consist of a number of 

 teeth curiously arranged. Although I cannot name 

 the beetle, I give a drawing (fig. 23S) from the 

 mounted specimen which I possess, as it affords an 

 interesting example of the variety of structure to be 

 found in the gastric teeth of beetles. 



Fig. 238. Gastric Teeth of Beetle x 120. 



Examples of other forms might readily be given ; 

 but since this paper is intended to be suggestive 

 rather than explanatory, it only remains that I 

 should give a few simple particulars relative to the 

 dissection and mounting of gastric teeth. 



The insect having beeu killed with chloroform, I 

 place it in a porcelain dish or saucer in water. I 

 hold it down firmly with a pair of tweezers, and with 

 the back of a dissecting-knife I draw the head 

 steadily from the body. The head, when separated, 

 brings with it the stomach, gizzard, and the chief 

 portion of the digestive tubes. All these I lay on a 

 glass slide, and place them under a simple dissecting 

 microscope : the gizzard being just below the 

 stomach and darker in colour, is easily distinguished, 

 and may be separated by two cuts with the knife : 

 it then forms a short tube, the teeth being iuside. 

 The opening out of this tube, especially if it be small, 

 is a work of some nicety, and requires delicate 

 handling : if the point of a fine knife can be fairly 

 inserted, then one firm cut downward upon the glass 

 will lay open the gizzard. Care should be taken on 

 this point, for a false cut, or a repeated effort, only 

 mangles the structure and destroys the object. 

 Sometimes it^ may be well to put a fine needle up 



the tube, and to cut down upon the needle, and so 

 open the tube. 



In the case of any small weevil, the whole gizzard 

 is so minute, and the membrane in which the teeth 

 are set is so delicate, that the most careful operator 

 will many times have to regret that in endeavour- 

 ing to open and display the structure he has made 

 a mess of 'a, beautiful object ; yet, if he have a real 

 love for the work, these failures will only add zest 

 to the pursuit, and enhance the pleasure of the 

 success that will finally attend upon his persevering 

 endeavours. — Lewis G. Mills, LL.B., Armagh. 



EOSSIL WOOD. 



THE lower group of the Lancashire coal forma- 

 tion gives character to the whole country 

 round the borders of the basin, rising up in long 

 low ranges of: green hills that flank the slopes 

 of the Pennine chain ; " and as they crop out " on 

 the hill-sides, or in the valleys, they are reached by 

 a perpendicular shaft of a few yards in depth only, 

 or by horizontal openings, locally called "Breast 

 hees." In the whole of this series there is, perhaps, 

 no seam so easily recognized as the " upper foot- 

 mine." Sharing, as it does, to some extent, the 

 family likeness common to the whole group — 

 mineralogical composition and identity of fossil 

 remains, — it is yet quite unique in some of its 

 features. Most of the seams possess some peculiarity 

 which distinguishes them from the rest, and which 

 serves the practical miner as a finger-post to guide 

 him in his labours. On none is the inscription more 

 legibly written than on the foot-mine. The feature 

 that gives it its peculiarity is the great number of 

 concretionary masses, locally known as " bullions," 

 which are invariably associated with it. Nodules 

 are to be met with in greater or less abundance 

 throughout the entire formation, interspersed 

 irregularly in the shale above the coal, while the 

 bullions in the seam of which we speak, thickly 

 stud the roof, and in many cases press in and 

 throttgh the coal, to the great detriment of the miner, 

 turning him aside in his work of excavation, and in 

 some instances rendering his labour unremunerative. 

 Indeed so serious a barrier do they sometimes 

 present, that he is often compelled to abandon the 

 attempt to recover the grimy treasure, and to 

 leave it locked in the unyielding folds of the "safe" 

 where Nature had hoarded it untold ages ago. 

 These nodules are of clay iron-stone with a slight 

 admixture of lime, and are so hard as to yield only 

 to repeated blows from a geological hammer of four 

 or five pounds in weight. The fossils they contain 

 are Goniatites, Orthoceratites, Pectens, Mytilli, a 

 few Ferns, Calamites, fragments of fossil wood, &c. 

 These stony remnants of extinct organisms are in 

 a good state of preservation, well defined in outline, 



