Sept. 1, 1SGS.J 



HARDWICKE'S SCIENCE-GOSSIP. 



215 



Feather Down. — Very little attention lias been 

 paid to the microscopical structure of the lower or 

 downy portion of feathers. It is true that a certain 

 peculiar type prevails in most (probably all) cases, 

 but this type is represented _ under variable phases ; 

 and a number of distinct microscopical objects may 

 be obtained from the feathers of birds. Let, for 

 instance, the down of the little Gold Crest be com- 

 pared with that of the Tawny Owl, and either of 

 these with that of the Cuckoo or the EiderDuck, and 

 it will be found that so much do these differ, the 

 one from the other, that the uneducated eye will at 

 once appreciate the beauty and variety of a class of 

 objects hitherto unknown, or but imperfectly known, 

 and inadequately valued. — M. C. C. 



Elephant Hawk Moth. — A friend of mine had 

 a larva about an inch long, of the Elephant Hawk 

 Moth (C. elpenor), brought to him about three weeks 

 ago, which was found on some bogbean about four 

 miles from here. We went there and found more 

 than twenty, and afterwards three or four on bed- 

 straw. I had four pupae out of those I found, 

 which changed about a fortnight ago. Eully ex- 

 pecting them to remain in the pupa state until next 

 June, imagine my surprise when, on looking at my 

 pupse this morning, I found two imagos emerged. 

 This seems extraordinary, as both the "Lepidop- 

 terist's Calendar" and Mr. Newman's "Moth 

 Nos." say that the moth is found in June, and the 

 caterpillar in August. Has any other entomologist 

 experienced this unusual occurrence? My friend 

 had a Poplar Hawk Moth (S. populi), apparently 

 fresh from the pupa, given him about a week ago. 

 Could this be from last year's larva ? — A. Mathews. 



The Mosquitoes at Woolwich. — Is there not 

 some misapprehension in supposing the insects 

 now investing Woolwich to be anything more than 

 common gnats, born and bred in their native home, 

 the tide ditches of Plumstead and the opposite 

 Essex marshes, this year produced in greater abun- 

 dance by the unaccustomed heat, house-tanks and 

 water-butts all aiding in the increase of the enemy? 

 As the last stage of the gnat's growth is completed 

 in water, it does away with the notion that this 

 invasion of pests could have been imported in 

 transport ships from Bermuda, or that they are 

 mosquitoes at all. Surely the inflaming venom of 

 a gnat-bite is bad enough ! — W. B. 



Male Hops. — There is an idea prevalent among 

 hop-growersthat it is necessary to have a few male 

 plants growing in the hop-gardens; although they 

 are to all intents and purposes entirely useless, as 

 far as I can see, considering that the maturity of 

 the seed is a matter of no, or at least of very 

 secondary importance, and that the active principle 

 of the plant resides in the female flower. Accord- 

 ingly, here and there in the hop-grounds that I 

 have visited, male plants are to be seen. Can any 

 of your botanical readers tell whether, since the 

 seed is not wanted, there can be any foundation 

 for the supposition that they are advantageous ? — 

 F. M. N. 



Onions 'and Epidemics. — Like many other 

 things under the sun, the supposed discovery of 

 John B. Wolff as recorded in "Scientific American," 

 and' reprinted in Science-Gossip of last month, is 

 not by any means new. It is an old wife's or rather 

 nurse's remedy for the prevention of the spread of 

 infectious fevers, and I have often been warned by 



the latter class of useful beings to throw away all 

 cut onions, and especially to take care that they 

 were not used for food when sickness had been in 

 the house. Did an "old wife's saw" put Mr. Wolff 

 on the track to find the cause why the onion-eating 

 sailors were attacked with cholera more than the 

 others ? If so would it not have been more gallant 

 on his part to have given all due honour to the 

 ".old wives " aforesaid ? — Anna Maria Hall, Hack- 

 ney. 



Sticklebacks and Carp.— Some fortnight or 

 three weeks since, finding one of my tanks rather 

 overstocked with fish, I took out "three or four 

 carp, and an equal number of tench, and put them 

 into another tank containing sticklebacks. Almost 

 immediately after ^they were put there, the stickle- 

 backs set upon the carp and gave them no rest until 

 they died, which occurred in three or four days, not 

 one of them having more than a vestige of fin and 

 tail left. The tench have not been molested at all, 

 and remain with the sticklebacks apparently happy 

 and comfortable. This reminded me of an old farm 

 labourer in Warwickshire having told me when a 

 boy, that no fish would ever injure a tench, as it 

 acted the part of a doctor, and cured fish of all sorts 

 of diseases. — J. G. Oddly. 



Privet Hawk— The caterpillars of the Privet 

 Hawk Moth (Sphinx ligustri) are unusually early 

 in their transformations this year. I possess nine 

 chrysalides at present. Can any of your corre- 

 spondents inform me the cause of a disease rather 

 prevalent among them ? The hinder portion turns 

 quite black and hard : the caterpillar lives for a 

 time but soon dies. This morning (August 11th) I 

 found a young privet about an inch long under the 

 soil, exhibiting all the symptoms of the transforma- 

 tion into the pupa. What was he doing ? Was he 

 only going to change his skin ?— H. H. O'Farrell. 



Tenacity of Life in the Cockroach. — Your 

 readers will doubtless be made aware by yourself of 

 the recent discovery of a lizard in a nodule of iron- 

 stone at Brixham, Devon. I know not whether my 

 discovery was as extraordinary, but at any rate I 

 consider it very singular. Cutting a piece of stale 

 bread in two at dinner the other day, I bisected a 

 cockroach, the knife passing just across the top of 

 the body, or shoulders. To my surprise the head 

 portion extricated itself from the hole in the bread 

 (the surface of which bore the appearance of having 

 been eaten by the insect), aud walked some four 

 inches away. It then stopped, overbalanced itself, 

 and turned legs upwards, kicking away for about a 

 minute, when I ended its sufferings — if it had any, 

 which is doubtful seeing what it had previously 

 gone through. I have met with these gentry in bread 

 before, but they have always been dried up and 

 brittle. On crushing these household pests in 

 ordinary a white creamy substance exudes. In the 

 present instance, however, the body was filled with 

 a bright greenish liquid which ran freely out. In 

 this case the feelers were broken, but the legs were 

 perfect, the hinder ones did_ not exhibit any mus- 

 cular action, nor did the main portion of the body 

 show any signs of life. I send this to you thinking- 

 it may be worthy of record in your pages that an 

 ordinary cockroach should have endured the knead- 

 ing and baking process of the loaf, imprisonment 

 for two days, followed by decapitation, and then be 

 able to walk away with a comparatively nimble step. 

 —P. F. N., Brixton. 



