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HARDWICKE'S SCIEN CE- GO SSI P. 



The parched and withered appearance of the grass 

 at the end of summer assimilates so closely with 

 the hue of the grasshopper, &c., found at that time, 

 that were it not for their activity and heedless 

 leaps they would be scarcely discoverable. The 

 little blue butterfly {Polyommatas Alexis) perched 

 on the flower-head of the scabious or the corn blue- 

 bottle, is another familiar example of the protecting 

 influence of similarity of colour. The moths, as I 

 have already pointed out, will likewise afford the 

 entomologist several examples of this thoughtful 

 provision of nature. Sometimes, however, the same 

 power of ready concealment is given to the enemies 

 of insects, which are thus enabled to seize their 

 prey with greater facility. For instance, last 

 August I noticed a beautiful glossy-green fly 

 buzzing loudly in a bramble blossom, and trying 

 hard to extricate itself. I thought, of course, that 

 it had been caught by the blossom, and that I had 

 discovered the latter to be a genuine fly-trap. On 

 gathering the blossom, and pulling at the fly, I 

 found that a spider of exactly the same colour as 

 the centre of the blossom had nailed the fly fast by 

 its proboscis, and ail its struggles to escape were 

 fruitless. I released it, but it was nearly dead. 



Several of the hairy caterpillars are no doubt 

 instinctively shunned by birds from the power they 

 passively possess of annoying, even in death, their 

 ornithological devourers. I allude to the urticating 

 properties of the spines in some species, the effect 

 of the punctures of which on the human skin is no 

 doubt familiar to every entomologist. Rennie 

 declares that no bird will eat the caterpillar of the 

 common Magpie Moth {Abraxas grossulariata) ; 

 but why he made this statement of a larva quite 

 smooth I am at a loss to understand. 



Lastly, it is possible that the ferocious appear- 

 ance, yet withal peaceful disposition, of some 

 insects is their sure protection. Look, for in- 

 stance, at the gigantic Stag Beetle, with its terrible 

 jaws, and you would think it perfectly able to cope 

 with anything ; but these dreadful frontal arrange- 

 ments are only useful in a passive sense, viz., they 

 serve to menace and terrify by their appearance, 

 and that is all. As weapons of defence in an active 

 sense they are, we believe, seldom or never used. 

 The Cocktail Beetles {Staphylinidm) and the Ear- 

 wigs, carry formidable forceps or pincers at the 

 tail, apparently for active defence, but in reality 

 they are simply used for tucking away the gauzy 

 wings under the short elytra. The most con- 

 sequential and impudent-looking of our British 

 caterpillars is that of the Puss Moth, whose atti- 

 tude when at rest is so well known. The cater- 

 pillar of the Elephant Hawk-moth (Chterocampa 

 Elpenor) is far from prepossessing in appearance, 

 the large ocellar spots on the skin on each side of 

 the body looking like a couple of great staring 

 eyes. The spines, spikes, and horns of many cater- 



pillars likewise give them a very ferocious appear- 

 ance, and probably insure them protection from 

 injury. 



This, I confess, is but a slight review of the 

 defensive resources of insects ; I therefore venture 

 to hope that some of the entomological readers of 

 Science-Gossip will send their experiences on this 

 interesting subject, and thus make the list more 

 complete. 



William Henry Warner. 



Kingston, Abingdon. 



SKELETON LEAVES. 



rriHE title is not very taking, certainly. It does 

 -*- not hold forth a promise of much interest, yet 

 if my readers, taking it for granted I am fortunate 

 enough to have any, could but see the exquisite 

 collection of skeleton leaves now grouped before me 

 (and which I owe to the kind courtesy of a corre- 

 spondent of Science-Gossip resident at Leicester), 

 they would, I am sure, quite understand why I have 

 selected such a subject. 



The process by which leaves are skeletonized— or 

 perhaps I should write, a process, for I am not 

 aware by what means the donor of the present col- 

 lection arrived at such perfection in the art — I will 

 describe at the end of my paper ; and meanwhile, 

 before I notice the different skeleton leaves in par- 

 ticular, just glance at the action or uses of leaves in 

 general, while they are on the tree. " Roots make 

 leaves, and leaves make roots," is an accepted say- 

 ing ; but then comes the explanation, that the above 

 wise-saw is good and true as far as it goes, but it 

 does not embody the whole fact, roots being made 

 without leaves, and leaves without roots. 



This appears at first a puzzle, nevertheless it is 

 true; but at the same time let me observe that 

 neither can live long without the other, save in the 

 case of plants which are not leaf-producing. 



The action of the root spriglet (the end of the 

 root) is much like the pulse in a human being, for 

 it never stops, night or day, in heat or cold, until 

 all vitality is at an end. Take a healthy tree as our 

 example, and we find that directly the roots, stems, 

 and branches are full of sap, the leaves burst forth ; 

 they are the lungs, and digestive arrangement also, 

 of the tree. They give out the watery portion of 

 the sap, by means of pores on the upper surface, 

 and then, when it is properly purified and rendered 

 sufficiently dense, they send it back to the root by a 

 set of vessels on the lower or uuder side. This ac- 

 counts for the very great number of veins which we 

 find in a skeleton leaf ; and thus it is that leaves, 

 when skeletonized, present so lovely and delicate an 

 appearance. 



I have now before me the exquisite leaves of 

 the ChnjsopJtyllum angustifolium and Ficus religiosa. 

 The former comes from the West Indies, where the 



