Mabch 2, 1912.] 



THE 



ARDEXERS' CHRONICLE. 



139 



in many cases and withstood the drought, 

 the best being the broad-leaved species. 

 Of the Conifers, Scots Pine suffered 



dividual brandies being as much as 20 inches 

 in circumference. The plant is growing on 

 elevated ground, and is sheltered on the north 



and the absence of segregation in the hybrids. 

 Further investigations into this rase are neces- 

 sary before a positive statement can be made. 



little whilst the Corsican Pine flourished side, but is fully exposed to the south. Yucca Having reviewed, in these le tares, many of the 



remarkably. The latter tree is a very 

 valuable species for planting in hot, dry 

 places, as it resists drought well, grows 

 at an enormous pace and yields valuable 

 timber. 



Apart from the fact that Spruce and 



gloriosa is a favourite plant for town garden- difficulties which prevent the acceptance of the 

 ing, and in suburban districts it is commonly theory of natural selection as an explanation of 

 employed as a centrepiece to the garden fore- the processes by which evolution has come to 



court, taking the place of the conventional vase. 

 The flowers are white or pale creamy-grey. 



Professor Bateson on Genetics.— In the 



pass, Professor Bateson said that, nevertheless 

 the great mass of evidence leads to the belief 

 that evolution has taken place. Historical ex- 

 amples of evolution are rare, but in the phe- 



Larch should never be planted together last lecture of his course, Professor Bateson nomenon of mechanism there are some interesting 

 on account of their intimate connection a « ain laid stress on the difficulties of applying cases . For instance| quite recently several of the 



in the spread of aphis attacks, which 

 probably are followed by Larch canker, 



the theory of natural selection in a vast number 

 of cases of specific variation. If it is to natural 

 selection that specific characters are due, then it 



inhabit contiguous areas we should expect to find 

 transitional forms in the intermediate districts. 



there is another reason against this mix- is evident that whm two nearfy Mie j spe( ies 

 ture, which was noticed last season. In 

 every case where the two species have 



been planted side by side, the Larch suf- But, as a rule, a mongrel population is found, 



fered badly from drought, owing to the consisting of hybrids, as in the case of Lychnis 



large quantities of moisture absorbed by dioica and L. vespertina, and of the American 



British moths have given rise to black forms, 

 and these are gradually ousting the older types. 

 In the case of the pepper moth a black form ap- 

 peared near Manchester in the first half of the 

 19th centmv, and it has spread northwards, and 

 as far south as the London district. It has also 

 become established on the Continent, in the 

 neighbourhood of certain large towns, and it has 

 been suggested that the black colour has a sur- 



the superficial root-system of the Spruce, butterflies Basilarchia astyanax and B. arthemis. v ival value, where smoke has Madrened the sur- 



which suffered little. 



In many cases, the forms inhabiting contiguous 



Thuya gigantea, Cupressus Lawsoniana areas see ™ to be adaptive; for example, the 



and Birch showed themselves capable 

 of adaptation to either moist or dry con- 

 ditions. 



In older plantations the effects were 



not so marked. Larch, in mixture with 

 Beech or Chestnut, suffered less than 

 when grown pure or mixed with other 



Conifers. 



Many old stag-headed trees of Oak, 

 Elm and Beech did not survive the dry 



season. 



As many ponds and small streams 

 were dry during last year for the first 

 time for a long period, some of the 

 older Willows and Alders in such places 

 lacked moisture and died or, at the least, 



suffered. 



General remarks upon premature leaf- 

 fall cannot be made, as trees were 

 affected differently in this respect even 

 in the same locality. The Lime, however, 

 seemed to be the least affected, for most 

 trees of this species preserved their foli- 

 age until the usual time. 



In the nursery those plants which were 

 " lined out n in late winter or early 

 spring throve much better than those 

 transplanted later, as they were able to 

 establish themselves before the warm 

 weather began. Beech seedlings showed 

 this plainly in many instances. Nursery 



mountain forms of many species of plants, as 

 distinct from the lowland forms. In a gradual 



roundings. Nevertheless in certain completely 

 rural districts in England there exist strong 

 colonies of the black form. Again, in the case 

 of the Honeybird, Coereba, in the West Indian 

 Islands, the black form, which was first noticed 

 in the 'seventies, has nearly replaced the yellow 

 form. Yet it cannot be said that the dark 

 colouring has any special survival value. 



The Flowering of the Almond. — The first 

 flowers on a tree situated in a favourable position 

 in Wandsworth, five miles south-west of London, 

 expanded fully last Saturday, the 24th ult. Pre- 

 vious dates for the flowering of this tree are 

 March 11 last year; March 12. 1910; April 1, 

 1909; March 23, 1908; March 20, 1907; Febru- 



FlG. 56. — ROYAL INTERNATIONAL HORTI- 

 CULTURAL EXHIBITION. 



(Cup presented by the Royal Horticultural Society 



of Ire'and.) 



plants withstood the drought much better P^age from one set of conditions to another 

 fi .. • 1 . .• j U4- such as exists in ascending the ni^h Alps, it 



than those in young plantations, no doubt s » . , , .... . *. . tMrft4-M , 



ry 28, 1906; .March 7, 1905; and March 21, 



1904. 



Royal Horticultural Society.— The next 

 meeting of the Committees of this Society will 

 bo held on Tuesday, the 5th inst. On this 

 occasion there will be a special exhibiton of 

 Spring Bulbs, which will be continued on the 

 6th inst. At 3 p.m. on the 5th inst. a lecture on 

 M Stimulation of Plant Growth " will be 

 delivered by Prof. Armstrong, F.R.S., LL.D. 



New Class forthe R.H.S. DaffodilShow. 



In connection with the Daffodil Show to be 

 held at the Royal Horticultural Hall, West- 

 minster, on April 16 and 17, Mr. Chester Jay 

 Hunt, of Montclair, New Jersey, has offered 

 £1 10s., £1, and 10s., as 1st, 2nd, and 3rd prizes, 

 in an open class for six varieties of Leedsii 

 Daffodils, distinct, three stems of each, the 

 varieties shown to cost not more than two 

 guineas per 100 bulbs. 



Royal International Horticultural 



owing to the deeper cultivation of the ^ wQuld fce found Bufc> fa general> two 



nursery soil. distinct forms occur, and the problem is, how has 



the change from one to the other come to pass. 

 Although it is rare to find intermediate popula- 

 tions, on the other hand there are cases that 

 seem to fit in with orthodox views on the subject. 



virulent than usual. Pine-beetle, how- For instance, in Egeria, the speckled wood butter- 



might be expected that a series of transitional Exhibition—Wo are indebted to Sir Frederick 



Parasitic diseases and insect pests were 

 not generally very troublesome during 

 the hot weather. Aphis, Pine-weevil and 

 Larch canker attacks were rare and less 



not exceeding 



ever, was abundant in some places. 



Our Supplementary Illustration. 

 Yuccas rarely enjoy so favourable a season as 



fly, there are three European forms. The com- 

 mon English form is yellow. In Spain, and as 

 far north as Poitiers, in France, a brown form 

 occurs, and further north we come to a form 



_ ■ a a «■ 



intermediate 



that of last summer, when the flowering of the through Brittany and the Channel Islands. This 

 plants was a common occurrence in all parts of case Professor Bateson considered to be one of 



the country. In the Supplementary Illustration 

 is shown a single plant of Yucca gloriosa in the 

 gardens at Upper Hall, Ledbury, the residence 

 of W. A. ff. Martin, Esq. It developed no 

 fewer than 18 fine spikes of bloom. Mr. A. C. 



the most striking he could give of a transitional 

 form occupying an intermedia te area. Yet by 

 breeding experiments he had found that the 

 intermediate type is produced by the cross be- 

 tween the northern and southern forms. So 



Moore for the opportunity of illustrating the 

 Cup (see fig. 56) to be presented by the Royal 

 Horticultural Society of Ireland at the Royal 

 International Exhibition next May for the 

 best exhibit of flowering and foliage plants 

 arranged for effect in a spac* 

 400 square feet. The cup is a copy of a 

 celebrated piece of Irish plate known as the 

 Moira Cup, and was manufactured by Messrs. 

 West & Son, Dublin. 



Leaf Curl. — This common fungus disease 

 of Peach trees, grown out-of-doorr , is said by 

 Professor L. Cjssar (The Canadian Horti- 

 culturist, vol. 35, No. I, January 1912) to be 

 capable of control by the use ot Yime sulphur 

 spray. The spray fluid to be effective should be 

 of ordinary strength, 1 pint of the commercial 

 wash to 10 pints of water, and must be applied 



Matthews, the gardener, informs" us that "the that the intermediate population might be ac- early in the spring before the buds have begun 

 plant has a girth of 45 feet, some of the in- counted for by the crossing of the two types, 



to swell. 



