36 



THE GARDENERS 1 CHRONICLE. 



[July 14, 1888. 



large pans of C. niveum being very fine ; and C. bella- 

 tulum, which may be regarded as the finest represen- 

 tative of the group, being also in bloom. C. con- 

 color, C. c. Regnieri, and C. Godefroyse were also well 

 represented. This section of Cypripedium require a 

 warm shady place where cold currents of air cannot 

 reach them, and it is above all things necessary to 

 search out a place they like, for they may often be 

 brought from a bad to a good condition by simply re- 

 moving them to the opposite side of the house to that 

 they have been occupying. C. Veitchii, C. Pearcei, 

 C. ciliolare, C. Lowii, C. Haynaldianum, and others 

 were also in bloom. 



The Orchids in the cool houses which showed 

 good culture, exhibited some fine sprays on 

 Odontoglossum Alexandra; and other Odontoglos- 

 sums ; there were large pans of Promensea citrina 

 and P. stapelioides, and spikes of Epidendrum vitel- 

 linum majus : some few species of Lycaste, Sobralia 

 macrantha, Miltonia vexillaria and M. Roezlii, Epi- 

 dendrum nemorale, and E. oncidioides, Anguloa 

 Ruckeri, Oncidium bicolor, and other Oncidiums, 

 &c. The warmer houses having placed among them 

 fine specimens of Nepenthes, several Vanda teres in 

 bloom and bud, Saccolabium ampullaceum, some 

 showy Dendrobes, and then the Phalasnopsis-house 

 all the occupants of which are in a thriving condition. 

 In bloom are the pretty P. sumatrana, and the rare 

 violet-purple P. speciosa Imperator. 



Cryftochilus sanouinea. 

 This neat little scarlet-flowered Orchid may now be 

 seen flowering in the Kew collection ; its singular 

 flowers, however, recalling those of some Aloe or Gas J 

 teria-like plant, as the sepals are united into a tube 

 somewhat contracted at the apex, and terminating in 

 three small triangular lobes. This tube is pubescent 

 outside, and the margins of the lobes dark brown, 

 the rest being of an orange-red shade. The floweis 

 are borne in an erect, somewhat one-sided spike, 

 each in the axil of a long acuminate rigid bract, the 

 inflorescence thus presenting an appearance some- 

 what unusual among Orchids. The pseudobnlbs are 

 ovoid, and produced in tufts ; and there can be no 

 doubt that a well-flowered clump of it would prove 

 an attractive object. There is but one other species 

 of the genus, C. lutea, which has somewhat smaller 

 yellow flowers. Both are highly interesting little 

 plants, and are found in various localities in the 

 Himalayas. The name refers to the concealed lip, 

 which is not easily seen, on account of the narrowly 

 tubular outer perianth. C. sanguinea was originally 

 discovered by Wallich on one of the mountains of 

 Nepal. B.A.R. 



DEFICIENCY OF COLOUE IN 



APPLE BLOSSOM. 

 In the Gardeners' Chronicle of June 23, " D. T. F.'' 

 asks why the want of colour in the blossom should 

 portend a defective crop of fruit ? He has himself 

 answered the question by suggesting that the absence 

 of colour indicates debility. This is, no doubt, the 

 immediate cause of the defective crop ; but why 

 should debility induce pale flowers ? Probably the 

 true explanation is, that the colour of a flower is 

 due to the condition of the [substances mixed with 

 the] protoplasm contained in the cells of the corolla. 

 This protoplasm is brown in the bark, green in the 

 leaves, and usually of various bright colours in the 

 flowers. In the green state it feeds upon the carbon 

 in the air, and thus replenishes itself, increasing in 

 quantity as the leaves expand. In the flower-bud the 

 green colour is lost, and it can no longer feed upon the 

 air, or increase in quantity ; the flowers must therefore 

 depend upon the amount of protoplasm in the bud at 

 the time of opening. This protoplasm has to be used 

 up in making new cells for the enlargement of the 

 corolla. If there be only just enough for this pur- 

 pose, the cells when formed will be empty, and the 

 flower will be white. If there be a small surplus of 

 protoplasm it will form coloured streaks along the 

 veins, or spots, or diffused tints. If there be a large 



surplus the flower will be entirely and brilliantly 

 coloured. The amount of protoplasm in the bud 

 will depend partly upon the constitution of the species, 

 and partly upon the propitiousness of the season. 

 It is the latter contingency which makes the paler 

 flowers indicate unusual debility, and therefore danger 

 to the crop. The normal colouring of the flowers 

 depends upon the constitution of the species, and 

 this is dependent mainly upon its position in the 

 life-wave of its genus or family. In the evolution of 

 the vegetable world the production of brightly 

 coloured blossom is the last and latest stage ; only 

 the most advanced groups have as yet attained to 

 that stage. In the order Rosaceae the genera Pyrus 

 and Prunus, to which our orchard fruits belong, are 

 not among these most advanced groups. They are 

 mostly in the stage of white blossom. The Apple 

 is more advanced than the Pear, Plum, or Cherry, 

 and has more colour in its corolla, because there is 

 a greater concentration of protoplasm in the flower- 

 bud, and therefore some surplus after the formation 

 of the corolla cells. The colours which indicate the 

 most advanced condition are yellow, rose-purple, and 

 blue. These are the true secondary colours, and 

 indicate that the molecular condition of the proto- 

 plasm has arrived at the maximum of concentrated 

 simplicity. The molecular vibrations are nearly 

 uniform, and will absorb only one of the three 

 primary groups of colour-waves in white light reflect- 

 ing to the eye the whole of the other two groups, 

 and thus presenting the greatest possible brilliancy 

 of coloured light. F. T. Mott, Birstall Hill, Leicester. 



Plant Notes. 



HELIONOPSIS JAPONICA. 

 This seems to be the proper name for a plant 

 described in the Gardeners' Chronicle, 1887, vol i., 

 p. 711, under H. umbellata. It proves to be a most 

 interesting plant, perfectly hardy in the open air, 

 doing well with treatment similar to that given to 

 Helonias bullata, and other plants of this nature. 

 The rose-coloured flowers, of medium size, are borne 

 two or three together on a raceme, 2 or 3 inches 

 above the compact rosette of lanceolate light green 

 leaves. It belongs to the Liliacea? family, and is a 

 native of Japan. Propagation is readily accom- 

 lished by division. 



TrACHYMENE C03RULEA 



is a very charming annual, extremely pretty for pot 

 culture as well as for cutting from. Seeds sown 

 during the autumn make good pots for present 

 flowering. Six or eight should be pricked off into a 

 32-size pot as soon as they are ready to handle, and 

 kept in a cool house or frame until they flower. It 

 is also interesting on account of its flowers being 

 blue, this colour being rare in the order Umbel- 

 liferse, to which this plant belongs. This plant was 

 figured in the Botanical Magazine, t. 2875, under 

 the name of Didiscus coeruleus. 



ElCHOBNIA PANICULATA, 



or as it is named in the Botanical Magazine, 5020 

 — where it is figured — E. tricolor, seems to be 

 a species that has not received much attention of 

 late years from cultivators of tropical aquatic plants. 

 When planted in groups consisting of four or five or 

 more plants, it makes a very attractive and showy 

 mass. It is very free-flowering, lasting in bloom for 

 a long time. It forms a very attractive object 

 planted out in a tub in one of the houses of the 

 Botanic Gardens, Cambridge, where it has been in 

 flower for some time past. The plants were raised 

 from seeds sown in February. They grow from 1 to 

 2 feet high, 'and close their flowers at night like 

 E. azurea, which is also planted in a tub standing by 

 its side. This is not such a free-flowering species as 

 the one in question, but perhaps bears the most 

 beautiful flowers. D. 



Chrysanthemum hematoma 

 This Chrysanthemum in its native country bears a 



profusion of lovely pink flowers, and I have been 

 told by those who have resided for some length of 

 time in Madeira that it is an extremely handsome 

 species. Mr. Lowe, in his description of the plant in 

 Madeira, says that it is " one mass of lovely rose- 

 pink flowers, and conspicuous from afar, like a 

 Camellia or Rose bush — is truly a splendid and sur- 

 prising sight." Plants sent from Madeira have 

 bloomed in the Botanic Gardens, Cambridge, and 

 the flowers were pure white ; but plants that have 

 flowered more recently have a distinct tendency to 

 become rose-coloured, and one we noticed the other 

 day, which had been planted outside in a very sunny 

 situation, quite a rose colour. Strong sunlight, no 

 doubt, is the essential required for realising a like- 

 ness to the description given above by Mr. Lowe. 

 Some of the flowers have been fine and large, 

 measuring as much as 3.J- to 4 inches in diameter. It 

 is of too straggling a habit for it ever to become a 

 favourite pot plant. It is quite distinct from either 

 C. frutescens or C. Brousonetti. Perhaps it might 

 be successfully crossed between one of the above- 

 named, so as to give it a better habit. W. H.., 

 Botanic Garden, Cambridge. 



IRIS KOEOLKOWI. 



The scientific zeal of Russian military officers and 

 explorers guided by the Nestor of Russian botany, Dr. 

 E. von Regel, of St. Petersburg, has within the last 

 twenty years brought to light many new plants from 

 Central Asia, and among them many new Irises. Of 

 these latter not a few are obviously allied to, and yet 

 in certain characters, differ from the group of Irises 

 known as the "Oucocyclus" group, of which I. Susi- 

 ana and I. iberica are well known examples. 



In these two Irises the most striking features, out- 

 side the large size and colour of the flower, are the 

 rounded orbicular form of the perianth segments, and 

 the dispersion of the hairs on the falls in place 

 of the compact beard of the ordinary Mediterranean 

 " bearded " Iris. These characters are correlated 

 with (1), large, generally inflated, and always persis- 

 tently green spathe-valves ; (2), a rhizome in which 

 the new buds instead of being closely adpressed to 

 old ones, are separated by a larger or shorter neck, 

 so that each bud stands out singly ; and (3), large 

 seeds with a conspicuous light coloured strophiole, 

 or appendage. These latter three characters are the 

 really distinctive characters, for in some Irises, such 

 as I. acutiloba, which certainly belongs to the same 

 group as I. iberica, the perianth°segments are narrow 

 (hence the name acutiloba), and in others equally 

 near to I. iberica the hairs are no longpr scattered, 

 but are gathered into a distinct beard. 



All the Oncocyclus Irises have a one-flowered 

 spathe, and the leaves, generally more or less falcate, 

 are as a rule not narrow in proportion to their length. 

 But several of the new Irises from Turkestan and 

 Bokhara, while agreeing with the Oncocyclus Irises 

 in the three characters just mentioned — of spathe- 

 valves, of rhizome, and of seed — especially the last 

 — have spathes which are two or three-flowered, and 

 leaves which are narrow and long. They thus form 

 a distinct group by themselves, to which I propose 

 to give the name Regelia. To this group I. Korol- 

 kowi, I. Suworowi, I. lineata (which I am now 

 inclined to regard only as a very distinct variety of 

 I. Suworowi), I. Leichtlini, I. vaga (which I am 

 similarly inclined to regard as only a very distinct 

 variety of I. Leichtlinii), and others belong. 



In this group, I. Korolkowi (named after a dis- 

 tinguished Russian general, who, unlike some of his 

 British analogues, does not regard it as below his 

 dignity to help the science of botany and the art of 

 horticulture), is distinguished by the large ovate- 

 lanceolate falls, which, narrowing gradually from 

 the blade to the claw, are flexed about half-way 

 down in such a way that the claws of the falls 

 embracing those of the standards form a funnel of 

 some length, from the mouth of which the blades 

 of the falls fall gracefully downwards, while the 

 elegant standards rise erect. Both falls and standards 

 are marked by more or less conspicuous but always 



