EECEEATIVE SCIENCE. 



857 



Several sections were made horizontal, ver- 

 tical, and diagonal, with the same result, 

 each showing cells with thick walls, and in 

 a few cells a central nucleus (Fig. 2, c). 

 Viewed with oblique light, the membranous 

 coating of the cell is beautifully seen. When 

 compressed between the compressorium, or 

 two plates of glass, a rupture of the cell- wall 

 is effected, and a drop of water, or glycerine 

 (glycerine answers best, from its greater 

 refractive power), being placed on the slide, 

 the contents of the cell are floated out, and 

 appear to be granules variously shaped. I 

 neglected to test for starch, but doubtless, 

 from the analogy of the nut, they would be 

 found to be principally composed of that 

 substance. Having proceeded thus far in 

 my researches in the healthy nut, and learned 

 thus much of its organization, I proceeded to 

 the examination of the diseased specimen. 



The diseased nut was apparently affected 

 with a malady, which had consumed it, and 

 it was no longer a very agreeable subject to 

 investigate, but the student of natural history 

 must not sicken at an unpleasant smell, or 

 shrink from an occasional disagreeable sight ; 

 such will sometimes afford him the best means 

 of instruction. Reasoningfrom the foetid odour 

 of the decayed nut, nitrogen entered into its 

 composition. The appearance of the shell 

 was as if it had been soaked in oil, doubtless 

 owing to the oily matter from the cells of the 

 nut being set at liberty, and decomposition 

 producing heat, thus rendering the oil more 

 liquid, and enabling it to permeate through 

 the walls of the shell. The kernel was 

 entirely decayed, no trace of cell being visible, 

 nothing remaining but a soft, oily, sugary 

 mass, of a dirty yellow colour ; the epidermis 

 was thinner than in a healthy specimen, but 

 exhibiting the same markings. My first 

 care was to remove a small portion of the 

 dirty yellow matter ; this was placed under 

 the microscope, with a power of 300 dia- 

 meters, and there stood revealed a reticulation 

 of thread-like fibres, beautiful in their con- 



fusion ; they were interlaced in every direc- 

 tion, a mere mass of fungi, the result, pro- 

 bably, of some errant spore released from 

 its parent stem, where it had hitherto nestled 

 under the tropical sun of Brazil, until having 

 arrived at a period when it became necessary 

 to procure its own subsistence, it started on 

 its voyage of life, and wandered along on 

 the wings of the gentle breeze until at length 

 it found a resting-place within this yet unripe 

 nut. Here it grew with its growth and 

 fattened upon its decay ; not a trace of cell 

 was visible, nothing but the threads ramifying 

 in every conceivable direction (Fig. 3). The 

 specimen was treated with various chemical 

 reagents, but nothing showed the structure 

 more distinctly than being merely mounted 

 dry, and covered with thin glass. When 

 viewed with oblique light, only a small pencil 

 of rays being permitted to fall upon the 

 fibres, they were found to be hollow tubes, 

 exceedingly delicate in appearance, but in 

 reality very tough and tenacious. Here and 

 there were to be seen small globular bodies 

 of what I conceived to be sporidia ; one par- 

 ticularly engaged my attention, as it rolled 

 gently over the field of the microscope, it 

 was studded with minute points, darker in 

 colour than the surrounding mass (Fig. 4). 

 Another specimen was examined, not quite so 

 much decayed as the first ; the same thread- 

 like fibres were to be seen, but with a dif- 

 ferent configuration (Fig. 5, a), and, crossing 

 the field was a dark brown line of vascular 

 tissue (Fig. 5, b). Probably owing to its 

 greater density in structure, it was enabled to 

 resist the parasitic fungi which had destroyed 

 so much around it. 



Here, then, was a lesson taught and 

 reflections suggested by a very simple sub- 

 ject, combined with the power of observation. 

 How many would have thrown it aside, dis- 

 gusted with its unpleasant odour, without a 

 thought that, disagreeable as it was, it yet 

 contained within it a vast mass of vegetable 

 life, supported by the same means, and 



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