HAKDWICKE'S SCIENCE-GOSSIP. 



283 



on, as indeed I believe it was everywhere. Regard- 

 ing my first theory, if Mr. Rees' Edusse had arrived 

 during the sunny days that preceded ' ' the four days 

 of continuous rain and north winds," I do not see 

 why they should have been spoilt by that bad 

 weather. I took in one morning, when the wind 

 was north-east, and squall after squall of heavy rain 

 came up, three of my best Hyale, and many good 

 clouded yellows. Of course they did not fly during 

 the rain, but in the only two intervals of sunshine we 

 had that day. For the three following days the 

 weather was so bad that I did not go out, but the 

 fourth day was warm and bright, and many speci- 

 mens were on the wing, though only one or two that 

 I saw were the worse for wear. Did all the Cardigan- 

 shire specimens hatch out on the morning that 

 Mr. Rees saw them, or if not, why were they not 

 spoilt by the bad weather ? I did not net a single 

 tattered fly till quite late in the month, though a few 

 were somewhat rubbed. I regret that I was not in 

 Suffolk at the time when hybernated insects might 

 be looked for, so I cannot say if they were observed 

 there this season. With regard to the theory ad- 

 vanced by Mr. Rees, it hardly seems to me more 

 probable than my own. The food-plant is always 

 abundant in Suffolk, and surely during the last fifteen 

 years, the weather, winds, temperature, and parasites, 

 cannot throughout that time, have been so adverse, 

 that the fly did not appear in, at least, limited 

 numbers. But during all those years, I have seen 

 very few Edusae indeed, though I have always been 

 in Suffolk at the time when they should emerge 

 from the chrysalis. Last year I did not observe a 

 single clouded yellow at all in Suffolk. On the 

 whole it seems to me that this vexed question is far 

 from settled at present. I do not profess to be 

 anything more than a mere elementary student 

 of natural history, and I hope that some of those 

 naturalists who have more time to devote to it 

 than I have, will soon give us a really good explana- 

 tion of the scarcity and abundance in different years 

 of Colias edusa. In conclusion, I should be very 

 glad to exchange some Suffolk clouded yellows for 

 Cardiganshire specimens, as it would be interesting to 

 note if there is any difference between them. If 

 Mr. Rees would care to do this, I should be glad to 

 hear from him about December iSth. Till then I 

 shall be in a different part of the country, and shall 

 not be able to get at my collection. — L. Creaghe- 

 Haward, Bramford, near Ipswich. 



In answer to Mr. R. C. Chaytor's query in the 

 November number of Sciexce-Gossip, I beg to 

 say that 52 feet 4 inches would be the length of a 

 three-quarter-inch diameter pipe to hold exactly one 

 gallon of water. — W. H. May. 



The same old Pipe. — In answer to the query on 

 page 263 of last month's issue, as to what length of 

 pipe J in. diameter it would take to hold one gallon 

 of water, I beg to say, if the pipe is quite true, and 

 the other conditions exact, that it would take 52 feet 

 3f inches. — Owen Carter. 



Fruit and Blossom. — In your November number, 

 on page 262, you refer to an apple-tree bearing fruit 

 and blossom at the same time. A few weeks since I 

 noticed a similar occurrence on an apple-tree in the 

 garden of a house in Mount Ephraim Lane, 

 Streatham. There was certainly fruit on the tree, 

 though perhaps not much, and quite a number of 

 bunches of blossom. The tree was very bare of 

 leaves. — W. I. Horn. 



NOTICES TO CORRESPONDENTS. 



To Correspondents and Exchangers. — As we now 

 publish Science-Gossip earlier than formerly, we cannot un- 

 dertake to insert in the following number any communications 

 which reach us later than the 8th of the previous month. 



To Anonymous Querists. — We must adhere to our rule of 

 not noticing queries which do not bear the writers' names. 



To Dealers and Others. — We are always glad to treat 

 dealers in natural history objects on the same fair and general 

 ground as amateurs, in so far as the " exchanges" offered are 

 fair exchanges. But it is evident that, when their offers are 

 simply Disguised Advertisements, for the purpose of evading 

 the cost of advertising, an advantage is taken of our gratuitous 

 insertion of "exchanges," which cannot be tolerated. 



We request that all exchanges maybe signed with name (or 

 initials) and full address at the end. 



Special Note. — There is a tendency on the part of some 

 exchangers to send more than one per month. We only allow 

 this in the case of writers of papers. 



To our Recent Exchangers.— We are willing to be helpful 

 to our genuine naturalists, but we cannot further allow dis- 

 guised Exchanges like those which frequently come to us 

 to appear unless as advertisements. 



"Sceptical." — Consult Taylor's "Sagacity and Morality 

 of Plants," chapter entitled "Turning the Tables," for full 

 information on the point you seek. You have got hold of a 

 half-truth. 



F. St. J. Parker. — Your insects are a species of the 

 suctorial Hemiptera (the Aphis, or green fly), and belong to 

 the order of insects known as hemipterous, or half-winged. 

 There are about 350 species of this order in England. 



F. H. Weeks. — The plant you enclosed last September got 

 mislaid, hence the delay in replying to your query. It is the 

 chervil (Ckteropkyllum temulum). 



"Entomologists." — By applying to the Secretary of the 

 Entomological Society of London, at 11 Chandos Street, 

 Cavendish Square, W., for all the rules and regulations 

 necessary for election to the fellowship of the society. 



A. C. Ward (Southampton). — Many thanks for the curious 

 growth of a violet leaf from your garden. The stipulate, or 

 flattened part of the leaf-stalk, is apparently unusually en- 

 larged through the attacks of a fungus. 



C. S. Watson (Donegal). — Many thanks for your very kind 

 offer of articles, but at present we have so many on hand that 

 it is impossible to undertake the responsibility. 



James Murray (Whitehaven). — One of the best catalogues 

 of plants on the flora of Cumberland, etc., is contained in the 

 late Miss Martineau's " Guide to the English Lakes." Doubt- 

 less you will get the best and readiest information by applying 

 to the Hon. Sec. of the Cumberland Association for the 

 Advancement of Science, Keswick. 



EXCHANGES. 



Magnificent triple lantern by Steward, together with 

 microscopic attachment, two aphengescopes, etc. Will take 

 part exchange in electric apparatus, telescope, or working 

 models of engines. For full particulars— Lyddm, West Park, 

 Clifton, Bristol. 



Wanted, Science-Gossip for 1873 and 1874. — T. A. Pear- 

 son, The Willows, Milnrow, near Rochdale. 



Wanted, Succinea oblo?iga, Acicula liueala, Helix car- 

 lusiana, Zonites excavatus, Bulimus ovscurus. Helix ter- 

 restris. Good exchange in British or foreign shells. — Mrs. 

 Carphin, 1 Lauriston Park, Edinburgh. 



An Andrew Ross \ objective, in perfect order. Will ex- 

 change for a \ Ross, Swift, or Powell and Leland. What offers? 

 Address — Vicar, St. Stephen's, South Lambeth, S.W. 



Offered, L. C., 8th ed., over a hundred duplicates, in- 

 cluding 45, 76c, 121, 144, 163, 186, 254, 280, 283, 571, 621, 646, 

 6gi, 784, 807, 829, 1107, 1237, 2155^, 1215, 1414, 1434* i577^» 

 1592, *595i 1697, 1777. Lists exchanged. Wanted, rare British 

 phanerogams and mosses. — Miss E. Armitage, Dadnor, Ross. 



Duplicates. — P. roseum, P. fontinale, vars. cinerea, pul- 

 cltella, and henslowana, P. pusillimi, P. nitidum. Deside- 

 rata, S. ovale and II. aspersa, var. exalbida.^ None but 

 specimens thoroughly cleaned and in good condition offered or 

 wanted. — Charles Oldham, Ashton-on-Mersey. 



One dozen good, large, and perfect carboniferous fossils 

 given in exchange for one good specimen of any of the follow- 

 ing varieties of silica : aventurine quartz, citrine, liver-opal, 

 float stone, moss agate, prase, ribbon jasper, sardonyx. — P. J. 

 Roberts, 11 Back Ash Street, Bacup. 



