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HUTCHINSON'S POPULAR BOTANY 



such abundance that I had to hold my head over a basin for an hour. The 

 sting is very virulent, producing inflammation ; and to punish a child with 

 'mealum-ma' is the severest Lepcha threat." The writer explains in a 

 footnote that the hairs are microscopically small, and they only sting 

 violently during the autumn. M. Leschenault, a French botanist who had 

 the misfortune to be stung by the " mealum-ma '' at this particular season, 

 while gathering one of the leaves for his herbarium, describes the symptoms 

 that followed as anything but pleasant. At first he felt only a slight 

 pricking which he wholly disregarded ; but the pain gradually increased, 

 and at the end of an hour it had become excruciating. The parts affected 



the first three fingers of his left hand felfc 

 as though they were being rubbed with a 

 hot iron. Before long the pain had spread 

 up the arm to the arm-pit : and within five 

 hours of being stung the torture was increased 

 tenfold by an ominous contraction of the 

 muscles of the jaw, which made him fear an 

 attack of lockjaw. However, the latter symp- 

 toms passed away towards evening, and from, 

 that time the pain continued to decrease, 

 though upwards of nine days elapsed before it 

 ^^H^^^^K^ entirely left him. 



^W\ That the inferior animals are sensitive to 



"^^ the stings of plants no less than man, and 



therefore that stinging hairs may be a real 

 protection from grazing animals, is illustrated 

 by the fact mentioned by Baillon, that the 

 natives of Java rub buffaloes with a species 

 of Nettle (Urtica stimulans) in order to excite 

 them to fight with tigers. On the other hand, 

 these vegetable fangs are innocuous to certain 

 leaf-eating insects, which feed upon them 

 with impunity ; indeed, it is well known that 

 the leaves of our British Nettles, which are all furnished with stinging 

 hairs, form the only food of the caterpillars of three of our most beautiful 

 butterflies namely, Vanessa atalanta, V. io : and V. urticce. But this fact 

 affords us a very striking object-lesson on the way in which an offensive or 

 merely defensive development in one organism may lead to the very con- 

 siderable adaptation in some other organism that may ba seriously affected 

 by it. The three caterpillars named have developed protecting spines 

 which keep the stinging hairs of the Nettle from contact with their tender 

 skins. Their relative, Pymmeis cardui, which feeds on Thistles, is similarly 

 protected. It is remarkable that, so far as we have read, botanical writers 

 have failed to note that hairs similar to those of the Nettle, but in a far 



FIG. 373. NAIL-GALLS 

 On leaf of Lime, produced by a r 



