JJoody Fibre of the Palm. 489 



trap sold in the shops for beetles and cockroaches, which is very 

 effective ; and frogs, toads, and hedgehogs, are exceedingly 

 useful in gardens for devouring insects. — Cond. 



Art. III. Remarfcs on the Origin and Direction of the luoody Fibre 

 of the Stems of Palms. By James Main, A.L.S. 



I AM induced to offer a few remarks on a paper read to the 

 British Association for the Advancement of Science, at Liver- 

 pool, on Tuesday, Sept. 12. 1837. The paper is said to be, 

 " Some Observations on the Origin and Direction of the Woody 

 Fibre of the Stems of Palms." Among other particulars relative 

 to their habitat and dimensions, it is added, that " In longi- 

 tudinal sections of the stem of a large species, the bundles of 

 woody fibre were distinctly seen passing from the scars and 

 bases of the leaves downwards and inwards, gently curving at 

 an angle of 18°, till they nearly reached the centre of the stem; 

 then, changing their direction outwards, they continued their 

 downward course with greater obliquity than before, till they 

 approached the external surface of the stem; after which they 

 still descended in a line parallel with its axis, ultimately be- 

 coming so much ramified, that it was impossible to trace them. 



" To Dr. Lindley's supposition, that the hardness of the 

 exterior cannot be owing to the outward pressure of new matter 

 from within, but to some cause analogous to the formation of 

 heart wood in exogens, Mr. Gardner replies, that a longitudinal 

 section of a palm stem, with leaves attached, clearly shows that 

 the ligneous substance is formed by the leaves; and this affbi'ds 

 collateral evidence of an analogous formation of the wood in 

 exogens. The only difference between the formation of these 

 two kinds of stems seems to be, that in the exogenous tribes 

 the woody fibre always remains between the bark and the last- 

 formed layer; while, in the palms, the bundles of woody tissue 

 first pass downwards and inwards to the interior of the stem, 

 then curve outwards, and finally run down parallel with the 

 axis, through the previously formed tissues which constitute the 

 column." 



The gravamen of the above quotation certainly appears to be 

 this ; namely, that the woody fibres of both exogens and indo- 

 gens are formed by the foliage of the former, and the fronds fo 

 the latter. I know well that this hypothesis has been embraced 

 by many eminent men; but it really appears to have been pro- 

 pounded without reference to the phenomena it was employed 

 to explain. That leaves can acquire existence before the parts 

 to which they are so intimately attached, from vv'hich they sprang, 

 and which nourish and support them, is rather illogical ; and why 



