March 1, 1S6S.] 



HARDWICKE'S SCIENCE-GOSSIP. 



C9 



perature ; arid there is in this respect no special 

 unlikeness to other fluids and solids in ice floating 

 on water. — Edwin Holmes, 1, Denbigh Terrace, 

 Bridge Road, Battersea. 



The Herbarium Insect. — In answer to " B.'s " 

 query as to the best mode of getting quit of this 

 troublesome enemy of collectors, I should suggest a 

 weak solution of corrosive sublimate iu water, with 

 which the specimens may be painted over with a 

 camel's-hair brush. A collection of N. Indian ferns 

 in my possession for the last twenty years were 

 gummed ; to their papers, and some corrosive sub- 

 limate mixed with the gum, and an insect is rarely 

 seen amongst them. But gumming specimens all 

 over does not improve them. — M. H. 



Herbarium Insect.— If " B." will put his dried 

 plants into a tin or other close box with one ounce 

 of benzine sprinkled amongst them, he will have no 

 difficulty in getting rid of the insects. If this is done 

 twice, at intervals of a week, he may feel quite secure. 

 Carbolic acid will answer quite as well, but the smell 

 is more permanently offensive. In mounting plants on 

 paper, it is a good plan to mix bichloride of mercury, 

 one grain to the ounce, with the gum which fastens 

 them down, or wash them over with a solution of it 

 in water, which should not be strong enough, when 

 dry, to soil a black feather ; it may then be applied 

 with success to prevent mildew on birds' eggs, in- 

 sects attacking dried bird and animal skins, insects, 

 or other dried animal or plant substances. Charles 

 Waterton preserved all his animals in this way. 

 Eor a permanency camphor will keep insects away. 

 —C. O. G. Napier, F.G.S. 



Herbarium Insect (p. 45, vol. iv.) — My 

 herbarium, having been once infested by this insect, 

 I have, for the last eight years, applied the follow- 

 ing solution (with a camel's-hair brush) to all my 

 specimens, and have not seen an insect since :— 

 bichloride of mercury, 32 grns., rectified spirits of 

 wine,' 8 oz., camphor, 5 grns. It requires care in 

 using, as it is a violent poison. — S. M. P. 



Hanging Plants— I too have observed that 

 many plants have the under surfaces of their leaves 

 of a purple hue ; but it is not, I think, confined to 

 the under surface, or to plants exhibiting a climbing 

 or hanging tendency. The Privet {Ligustrum 

 vulgare) very commonly has the whole of its leaves of 

 a dusky purple ; many species of Trifolium also, and 

 some maritime plants, more particularly those of the 

 genera Sueda, Salicomia, or Atriplex. I cannot 

 account for the circumstance, unless it is due to a 

 chemical change taking place in the chlorophyle or 

 colouring matter of the leaves ; but L hardly think 

 any one theory will account for it. Chemical change 

 is propably the reason that such plants as Sueda 

 maritima turn reddish-purple, because it always 

 seems to occur (in common with some other plants) 

 at one particular period, and invariably just before 

 its final decay ; but we must, I imagine, account for 

 the abnormal colour in some other way, in such 

 plants as Linaria cymbalaria, or the Copper Beech. 

 I believe the question has been mooted before, but 

 I think not answered with any degree of certainty 

 as yet. — G. T. N. 



Artificial Sandstone. — Under the ruins of 

 Sandown Castle, Deal, is what at first appears to 

 be a soft yellow sandstone ; but is only the sea- 

 sand petrified by the lime washed down by the rain ; 

 it extends nowhere beyond the castle, and is full of 

 common shells. — H. C. L. 



Hedgehogs. — These animals are certainly om- 

 nivorous ; I cannot therefore agree with Mr. W. I. 

 Sterland (p. 23) in " very much questioning whether 

 they would eat apples and pears." They may 

 possibly prefer animal to vegetable food ; for I have 

 frequently, when a lad, caught them in traps set for 

 vermin and baited with garbage ; also at the mouths 

 of rabbit burrows, which I imagine they were 

 entering with no peaceful intent ; nevertheless, they 

 are beyond question vegetable feeders also. In the 

 instance to which Mr. " S." refers— that of a hedge- 

 hog carrying off a number of pears by rolling itself 

 on them, and which I transferred to the pages of 

 Science-Gossip from a German periodical, the 

 narrator states that he actually witnessed the oc- 

 currence. This, coming from an anonymous corre- 

 spondent, must be taken only for what it is worth ; 

 but then the writer states besides that he saw 

 several little ones in the hedge which enclosed the 

 garden awaiting the coming of their prickly parent. 

 Now, I think it very probable that the hedgehog 

 may in its infancy live exclusively on roots, fruit, 

 &c. If this is conceded, the story is easy of ex- 

 planation. The matronly robber collects the pears, 

 not for her own eating, but for the support of her 

 progeny. Whether she can herself remove the fruit 

 from her back by a vigorous shake, or by passing her 

 body under the stiff branchlets on the lower part of 

 a hedge, I cannot tell. But I have no doubt the 

 task of detaching it is easily accomplished by the 

 teeth and claws of half a dozen hungry young hedge- 

 pigs ; for, after all, the dorsal spines are very short, 

 and would scarcely enter the pear beyond its rind. — 

 W. W. Spicer, Clifton. 



Wooden Taps and Acari (p. 41).— It is scarcely, 

 I imagine, worth any one's while procuring Wedg- 

 wood's ware taps for the sake of avoiding acari. 

 We devour abundance of them (I mean, Acarus 

 sacchari) with the brown sugar used in the making 

 of tarts, &c. Let any one dissolve a little brown 

 sugar in a wine-glass of water, and, with the aid of 

 a lens, or even with the naked eye, he will probably 

 see plenty of them struggling on the surface of the 

 water.— W. W. S. 



The Madrona of California.— There is a tree 

 in California which a friend of mine, who has been 

 there for several years, tells me is called the 

 Madrona by some people, and by others the Chit- 

 timwood ; but his description of it does not quite 

 correspond with the appearance of the Arbutus 

 unedo. He says the Californian "Madrona" is a 

 species of Rhododendron (the Arbutus and Rho- 

 dodendron both belong to the same order of plants, 

 do they not ?) and that the berries are &pale red, very 

 abundant in autumn, but quickly eaten off by the 

 birds. The leaves are green all the winter, and 

 closely resemble those of the laurel of the Alle- 

 ghanies. Surely the berries of the Arbutus unedo 

 would be called a deep red. The most magnificent 

 trees I have ever seen of the Arbutus kind, are some 

 of the Arbutus unedo growing on a high hill over- 

 looking the sea at Kiilymaensewyd (the residence 

 of S. Hughes Rees, Esq.), in South Wales.— Helen 

 E. Watney. 



Erog Spaw t n. — When taking a " constitutional " 

 this morning (Feb. 9th), I noticed a quantity of 

 frog-spawn in a running stream ; this is earlier 

 than I have ever before seen it. Gilbert White in 

 his " History of Selborne," mentions the 28th of 

 February as the earliest date of its appearance — 

 C. S. B.G. 



