IX 



\J 11 IV U 1^1 XV^JUlZi 



BRITISH ASSOCIATION FOR THE ADVANCE- 



MENT OF SCIENCE. 

 Section D.— Dr. Lankester made a report from the 

 committee appointed to register the Periodic Phenomena 

 of Plants and Animals. He stated that during the past 

 year the committee had published in the Transactions of 

 the Association, abstracts of the papers which had been 

 returned to them. They consisted first of a series of 

 observations made in 1841) by James Hardy, Esq., at 

 Penmanshiel, Cockburnspath, Berwickshire/ Second, of 

 a series of observations made in 1849 and 1850, by 

 Matthew Moggridge, Esq., at Swansea, South Wales. 

 Thirdly a small number of observations made from 

 February to July, in 1849, by E. H.M. Sladen, Esq., of 

 Winfield,near Battle, Sussex. He had received this 

 year from Mr. Moggridge and Mr. Sladen, tables filled 

 up to the end of June, 1851, which he hoped would be 

 published in the next; volume of the Transactions. Dr. 

 Lankester stated that he had received these papers too 

 late to be able to compare the results with those 

 observed in previous years, but he made no doubt 

 that many of the members present had observa- 

 tions to make on the present remarkable season. He 

 then referred to some observations of Dr. T. Forster, 

 of Brussels, which had been recently laid before the 

 Linnean Society. In Belgium the family of Hirundinae 

 had been unusually scarce this year, and the house 

 martin had not been seen at all. The winter had been 

 unusually mild, the spring unusually cold. — Mr. Rodweli 

 observed, that he had been in the habit of noting the 

 periodical phenomena of birds, and never recollected so 

 great a scarcity of the swallow tribe as during the present 

 season. Both the cuckoo and the nightingale had been 

 ten days later than usual in making their appearance, as 

 also the ear- wig. — Mr. Peach had seen one swallow on 

 Good Friday last. The swifts were first to appear at 

 Peterhead. He had seen no sand martins, and the 

 house martin was very scarce. These observations, 

 however, were not comparative, as he had not had 

 opportunities of observing these animals at Peterhead 

 in previous years. — Mr. Bunbury had observed that the 

 very early spring plants had all blown unusually well, 

 as the Snow- drop, the Hazel, and the Winter Aconite. 

 During March and April no progress was made. The 

 swallows appeared about the 16th of April. All the 

 tribe of Hirundinse had, he thought, been as abundant 

 as usual near his residence, in the county of Suffolk. — 

 Mr. M 'Andrew observed that the martins and swallows 

 had been in unusual numbers this spring at Malaga, and 

 perhaps this would account for their scarcity in other 

 parts of the world. 



- ENTOMOLOGY. 



The Biamondb\cked Turnip Moth. 

 A correspondent in the agricultural portion of this 



paper of the 26th of July, in the present year, requests 

 information respecting u a new enemy to the farmer," 

 which in lieu of the ordinary Turnip-fly has come into 

 the fields in some parts of Cornwall, in the shape of a 

 tiny ash-coloured moth, not unlike the common clothes 

 moth, but smaller. The rows of Turnips are said to 

 swarm with them, and the underside of the leaves is 

 covered with their grubs, which commit great havoc. 

 In some instances they have cleared the ground as 

 effectually as the black caterpillar did some years ago. 



In the course of last week we also received from a 

 correspondent, "W. P. L.," specimens of this small 

 green caterpillar, which was stated to be at that time 

 devastating the Swede Turnip, to the danger of the ex- 

 tinction of the entire crop, in many parts of Notting- 

 hamshire, both on light and strong lands ; almost every 

 Turnip leaf being infested by many of these grubs. 



These larvae are not entirely unknown to the farmer, 

 nor, unfortunately, is the present the first season of their 

 appearance. In Mr. Curtis's valuable series of papers 

 on Turnip insects in the "Journal of the Royal Agri- 

 cultural Society," is to be found a notice of the 

 ravages of this insect ; but as Mr. Curtis has not 

 given a detailed account of its preparatory caterpillar 

 and chrysalis states, I have thought it useful to complete 

 the history of the species in the present article. The 

 following account of the ravages of the insects was sent 

 by Mr. J. Weaver, of Petersfield, Hants, to Mr. Curtis, 

 together with a specimen of the moth which he had 

 himself reared from the caterpillars in question, and 

 which had been exciting some surprise in his neighbour- 

 hood in the summer of 1837 :— " About the beginning 

 of August I was directed to a field of Turnips said to 

 be infested by the ■ niggers ;' they proved, however, to 

 be myriads of tiny larvae, averaging, perhaps, half an 

 inch in length each, slender, and somewhat tapering at 

 both ends, and of a green colour when full fed. They 

 were exceedingly active, and on the slightest touch 

 would wriggle themselves off from the leaf on which 

 they were feeding, let themselves down by a silken 

 thread, and remain suspended till the cause of alarm had 

 subsided, when they would regain their former position. 

 So incredible were their numbers, that on a single plant 

 of moderate size, and taken at random, 1 counted 

 upwards of 240, and before the end of the first week in 

 August every leaf for the space of more than an acre 

 was completely reduced to a parched up skeleton— not 

 a Turnip escaped them ; and by the middle of the month 

 you might have looked in vain for the smallest vestige 

 of a green leaf on the field of their depredations, and to 

 this day (Oct 29, 1837), it is as bare as if nothing had 

 been sown there. Similar patches may be seen in two or 

 three fields in thisneighbourhood,whereamost excellent 

 crop is yielded in every other part. On the 1 9th tney 



the segment succeed- 



■ began spinning their cocoons, which are of the most 

 beautiful net-like texture, some on the dead fibres of the 

 Turnip leaves, and others upon the ground. The 

 perfect insects emerged about the 20th." ^ (Journal 

 of Royal Agricultural Society of England, vol iii., p. 71.) 

 It is some consolation thus to learn that the insect is 

 comparatively partial in its attacks, a circumstance 

 probably owing to the fact that it is not confined to the 

 Turnip, which, indeed, from some unexplained cause or j 

 other, seems only occasionally liable to be infested by it. 

 The name of the species, Xylostella, indicates its ordinary 

 food, the upright Honeysuckle, Lonicera Xylosteum,butit 

 also attacks a great variety of culinary plants, especially 

 the Cabbage and Turnip. 



The caterpillars which I received from * W. P. L."are 

 not quite half an inch long, cylindrical, gradually 

 attenuated towards the head and posterior extremity of 

 the body, of a delicate pale green colour ; the head of a 

 yellower tint, with the minute eyes at the sides of the 

 front of the head black, and marked, especially behind, 

 with numerous small black dots ; 



ing the head, instead of being marked with two large 

 dark-coloured patches, as in the majority of these small 

 caterpillars, bears a number of minute black dots, three 

 on each side of the middle line, forming a triangle, and 

 emitting a fine black bristle like hair — others, at the side, 

 also emit similar hairs ; the second segment behind the 

 head is marked by a small yellowish, oval, transverse spot 

 on each side of the middle line, each bearing two small 

 black setigerous dots ; the third segment is similarly 

 marked to the second ; each of these three anterior 

 segments bears a pair of short jointed feet ; the fourth 

 and folio wing segments bear threeof these black setigerous 

 dots in a triangle, on each side of the middle line, with 

 two placed longitudinally at the sides. There are four 

 pairs of short ventral prolegs, and a pair at the extre- 

 mity of the body, which are more obliquely exserted 

 behind than usual. Being full grown, the caterpillars 

 sent by u W. P. L." have already spun themselves up in 

 their cocoons, attached to the top of the box in which 

 they were placed. The cocoon is very delicate, being 

 formed of an open net-work of fine white threads, allow- 

 ing the chrysalis within to be seen. The threads at the 



of the insect can be most 



* dif 



u size and zreat "«. v ? m 

 picking ; whilst th*i^!^ nu ?k** 



must be a matter of diftX ily ?****!* 

 their small siz« m A ** cult y with thT 



•i 





their habit TO^^Q 



side of the leaf prevents th* V^ 11 ^ <* ttf ^1 

 soot, or lime, or other ZZzT*^**^ 

 which would, of course? rest on,?** **«? 

 and so be prevented from c J f 7 ^ ** Sfr 

 bodies of the caterpillars Til * *«—*** 

 would suggest that the li me } 



ft 



co&fcet 



weather 

 soot, ' 



ends of the cocoon are not continuous, but appear to be 

 arranged somewhat in the same mann3r as in the cocoon 

 of the emperor moth, enabling the insect to perform 

 two important processes in its economy. After the 

 caterpillar has completed its cocoon, it seems to have 

 protruded its body out of the hinder part of the cocoon, 

 and then to have sloughed off its larva skin, withdraw- 

 ing itself gradually into the cocoon, leaving its old cover- 

 ing on the outside. (Fig. 1 b, represents the slough or 

 caterpillar skin, on the outside of the cocoon ; 1 c, the 

 open work cocoon, showing the chrysalis 1 d, through 

 its meshes.) In like manner, the chrysalis, or the 

 newly-hatched moth, is able to protrude itself with less 

 difficulty than in ordinary cases, through the opposite 

 end of the cocoon. 



The chrysalis is an interesting object, being of a 

 greyish white colour, with several black streaks down the 

 back and sides ; each of the spiracles or breathing 

 pores is protected by a small conical point, and the ex- 

 tremity of the body is furnished with several minute 



hooks, by which it attaches itself to the interior of the 

 cocoon. 



The perfect insect makes its appearance in from 10 to 

 18 days, and is systematically known under the name 

 of Tinea (Cerostoma) Xylostella. It measures rather 

 more than half an inch in the expanse of the fore wings, 

 which are long and narrow, with several pale spots on the 

 fore margin, and a continuous white or ochraceous stripe 

 I on the hinder margin, with several indentions on its fore 

 j edge, which, when the wings are closed, form a row of 

 pale diamond-shaped spots down the back ; the hind 

 wings are ashy-coloured, with very long fringes 

 According to M. Dunonchel there are two generations 

 of this moth in the year, the first appearing in 

 June, and the second at the end of the summer * but 

 Mr. Curtis considers that in this country there' is a 

 succession of broods from Midsummer until the approach 

 of winter, as he had taken specimens in the gardens 

 near London, at the end of June, at Dover in July, in 

 Scotland in August, and frequently amongst the Turnips 

 in September and October, in Suffolk and Essex. It is of 

 course of considerable impor ance to determine the period 

 of the appearance of the insect in its perfect state, as it 



seems to me that it is at that time that the <W.mr.tinn 



wouia suggest that the li me *">***> **m* 

 matters obnoxious to the taste W^ ' J °4»S 

 be made into a thick liquid b V the £i t 7 plB ^2 

 or soapsuds, and that the plants sh oS °l «**5 

 this mixture several tint (J^^J^WS 

 will not be difficult) ; by this means *1>'"*kS 

 rendered unpalatable J the Sjajj ^Sf 



fee insects i appyrfng in the perfect^ 





* 



ascertained and then a net or bag mi'htLT^k 

 the plants, the nnder side being Credit 1 ** 

 any other adhesive matter ; and if on! ,* * 

 be raised, the moths will be prevented * ki 

 from rising and flying off, but will be ZJu* 

 sticky under-side of the net. An «£»£ » 



^ y jTm the best kbd of - ^ 



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Home Correspondence 



' The Crystal Palace.— The question is not ^ 

 Crystal Palace shall remain to please either «***• 

 or another, but how far it will conduce to the - 

 and convenience of the inhabitants and visita?!? 

 metropolis. The alterations in the building £?? 

 out the gardens, will require a vast outlay' whU 

 be met by the surplus in the hands of the pI LS 

 If money is forthcoming there can be no doulbtSeX 

 case may be converted into a permanent winter \om 

 Walking amongst Camellias, Orange trees, AzalewS 

 &c, when snow is on the ground, would indeed W 

 untold luxury, and one that should not be lightly tbw 

 away, having everything within reach, except 

 certainty of the annual expenses for repairs mL 

 gardeners, &c, which cannot be estimated underVSp 

 or 15,0007. per annum— a large amount to be collect 

 from visitors admitted at a low rate. The garden** 

 be self-supporting, as the country cannot afford to a 

 for an immense London conservatory. Govern* 

 should have nothing to do with the managemeoMh 

 interference would probably ensure a failure. Let i 

 direction be vested in the hands of commissioners ; \ 

 world's bazaar has flourished under their guidance, i 

 there is every prospect of the garden doing the sin 

 The idea of a second exhibition cannot be entertaine; 

 such a gathering must be left for the next generation 

 call together. Top ventilation will be essential in i 1 

 conservatory. However, under the superintendence! | 

 Mr. Paxton, everything will be well considered, a 

 nothing left undone which ought to be done. The winf 

 garden will rather improve than deteriorate property 

 its neighbourhood, under stringent regulations. Noth; 

 should be done in haste to be repented of at leist , 

 Query. Should 35001. of the public money, in these hi I 

 times, have been voted for the Victoria Lily? Fakon | 



The Use of Salt on Garden-walks.— -There is noth; 

 new in the discovery that an excessive dose of salt, ei 

 in solution or in a dry state, will destroy vegetable lr 

 neither is it a novel proposition that the present 

 saline matters in a slight degree is favourable to 

 healthy development of Grass and weeds. Many y? 

 ago the subject underwent a good deal of discussioi | 

 the" Gardeners' Magazine ;" the letters of the faced 

 " Agrenome " upon that subject will, doubtte 

 remembered by many of my gardening friends of ^1 

 day. From these papers it may be inferred tfcatl 

 was then considered a valuable stimulant. Admij 

 fully the sterilising effects of excessive doses of si 

 hope to be permitted to say that I dissent entirely i 

 those who recommend its appliance in any fori 

 garden- walks. It renders them damp and slipper} £ 

 its deliquescent property ; it destroys oae crop w 

 reproduce another in greater luxuriance, alter a 



; 











time ; and it destroys "seeds, but forms a fit 

 the germination of ' others, which are watteu ~ 

 winds. This is not mere assertion, but tact, as i • 





proved over and over again. Mr. Forbes, of e* 

 field Nurseries, near Elgin, writing in I»; B '« 

 table in which he shows, with small exception, t, 

 proportion to the moderate nature « t^ »T 

 ing, the weight of his crops increased, wh.le « 

 creased in proportion as the quantity «3 

 lecture upon the use of salt, given ^ p rofe^>r 

 short time since, it was stated that Lord we. 

 had tried salt upon a road four miles ion , u ; 

 found to reproduce another crop in great iu- 

 the particulars of this experiment fwW^. 



Upon such authority it must be c° nsldere V. ie if<* » 

 The statement that one dressing is sun 

 season is an error which I have proven. • 

 two patches of a court yard here, up on *' ~ & 

 solution of hot water and salt was pouiea ^ 

 months ago ; the weeds then growing were ^ 

 has nosv growing upon it as fine a crop . # 



could be desired. *I regret that those who 

 the subject, either F -o or con, should ™ j^g 

 names, at their evidence would oe 01 & „ ^ 

 they had " a local habitation and a name. 



Nunekam. ... ,„„.. t ij e rfc** 



Irish Larks.-lfDr. M'Cormac will to« ^ » 

 to read my passing remarks upon w ' .,* 

 Ireland," once more,~he will hnd I spot 





