November 29, 1877. ] 



JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 



415 



considerably to add to our floral queen's admirer?. The Duke 

 of Edinburgh is a most pleasing brilliant flower, and (an ad- 

 ditional quality) is admirable for a button-hole. General Jac- 

 queminot, if not so full in early bummer as is desirable, he 

 will make ample amends in autumn; then be sports bis real 

 fox-hunting eloth and in more plenteous folds. Regarding 

 Gloire de Dijon, whose name accompanies all orders, or at 

 least all orders for the first dozen, perhaps this verv popular 

 Rose has made more Rose converts than any other Rose, and 

 I do think that there is nothing substantial to fall back upon 

 save downright prejudice when we see our old almost evergreen 

 friend's name excluded from the "best" forty-eight; in bud 

 it is unsurpassed. John Hopper you must be sure to have. 

 He is a good-natured accommodating old boy ; he comes up 

 again and again as blithe as a bee, and year after year. Louis 

 Van Houtte is a very fine dark Kose. For Mdlle. Eugenie 

 Verdier I have a great liking. She is robust and keeps her 

 box of points very much to herself. Her colour was, I think, 

 quite new when she first made her appearance. Marquise de 

 Castellane is a noble Rose — a real gem. Prince Camille de 

 Rohan must be had if only for a button-hole; I vote it the 

 most satisfactory dark Rose we have. Either Princess Beatrice 

 or Princess Louise will please, but perhaps the former is the 

 more robust. Next comes Senateur Vaisse. This has been 

 the best Rose I have had this Beason. I believe this ends my 

 dozen, but I find that I have not named a white ; well, I like 

 Bironne de Maynard best of all the whites, a free and charm- 

 ing Rose. Then we must add two Moss Roses, they are very 

 old favourites. Procure if possible the old common Mosb for 

 one, and the white Bith Moss grows very well. I have finished 

 my lot save one, and with reasonable fair play I believe they 

 will supply as much delight aud as few disappointments as 

 any other dozen that can be selected, and from either the 

 newest or the lengthiest of catalogues. Of the one alluded to, 

 this last summer its fine blooms supplied me with much 

 pleasure ; they were the renewed pleasures of old. I tended 

 to and nursed the old York-and-Lancaster when a child forty 

 years ago. How distinct its stripes are still ! How strange 

 that with such a foundation we have sent our old friend into 

 obsouiity, and to this day we have not been supplied with one 

 distinct striped Rose as a substitute. — Joseph Witherspoon, 

 Bed Rose Vineries, Cliester-le-Street. 



SPECULATIONS AS TO THE NATURE AND 

 ORIGIN OF THE POTATO DISEASE.— No. 3. 



As bearing on the subject of the Potato murrain the next 

 disease to be referred to is the Phylloxera which attacked 

 the Vine, and I cannot do better than refer to the Report 

 of the French Commissioners appointed to inquire into 

 this subject, and make an extract from it. " For some time 

 several large vineyards in the south of France have been 

 visited by a formidable and entirely new disease, and to which 

 the Vines on which it has seized succumb as a rule at the 

 end of the second year. This disease, the origin of which 

 is nnknown, appeared for the first time in the valley of the 

 RhOne during 1864 or 1865, but it was not until 1867 that 

 it had attained such a prevrfence as to excite alarm. In 1868 

 and 1869, however, it had become a regular scourge. Then it 

 was that those wholesale desolations of wide tracts of country 

 were seen, and which appeared to be so much the more de- 

 structive because the first appearance of the evil had perhaps 

 been overlooked. From this time the disease did not ceaEe to 

 spread, and it now rages from the department of La Drome to 

 the confines of La Cran, more particularly on poor, dry, stony, 

 and damp soils. The visible feature most characteristic of the 

 new disease is the existence of a centre of attack in those parts 

 which have been but a short time affected and which extends 

 itself without intermission. The portions of the Vine which 

 are contiguous to the tainted part let their leaves fall and grow 

 yellower and yellower until they are quite dried up. When 

 the seat of contagion has grown to a sufficient extent and when 

 the disease is severe enough, instead of one there spring up 

 several centres of attack. From the facts it has been generally 

 remarked that the disease is propagated in two ways, pro- 

 gressively and intermittently. The gradual extension of various 

 centres of attack of which we have just spoken shows us the 

 first ; their existence simultaneously at several far isolated 

 points is proof of the second. The concurrence of many in- 

 stances has taught us that the new disease of the Vine makes 

 its way by irregular bounds, often abruptly appearing at great 

 distances from the already ascertained centres of contagion. 



When the roots of the afflicted Vines are examined it is easy 

 to see that they have considerably altered in their nature, for 

 they are always soft and rotten, and the tissues surcharged and 

 without any firmness, yielding to the pressure of the fingers. 

 These severe affections are due to a kind of insect which has 

 been named the Phylloxera vaatatrix. This insect, which is 

 almost invisible to the naked eye, takes up its abode in the 

 roots of the Vine and pricks tbem with its proboscis in order 

 to extract the juices they contain. These repeated perform- 

 ances most likely irritate the tissues and produce hypertrophy. 

 Until now there is not a single kind of French Vine which has 

 not been attacked by this disease, but it is reported that there 

 are some American varieties in the outskirts of Bordeaux 

 which, although they have been surrounded by infected plants 

 for three years, show no signs of suffering from the new com- 

 plaint. According to the recently-made investigations the 

 Phylloxera exists under two different forms — wingless and 

 winged ; it is not viviparous, but during the whole season and 

 under both forms it only deposits eggs. They hybernate on 

 the root of the Vine as wingless insects, and never in the egg 

 condition. So long as the weather is severe they remain in a 

 state of perfect torpor, but as soon as the warmth begins to 

 make itself felt all those individuals which the cold and damp 

 of the winter has spared begin to wake to renewed life. They 

 feed with great avidity, and begin to lay eggs. The increase 

 of them soon becomes terrific aud never stops till October, and 

 it is during this time that the Phylloxera works terrible 

 havoc." 



It will be observed that here is the introduction of a new 

 disease not observed before 1864, and that the American Vines 

 escape the attack, and that the insect appears to exist in two 

 forms on the leaves and underground. The disease is supposed 

 to have been of American origin ; and if it only attaoked the 

 American Vines on the leaves and for some reason or other 

 did not attack their roots, which appears to be the case, the 

 insect might have existed there ever since the world began 

 without doing any serious injury to the plants, but directly the 

 insect came into contact with European Vines and attacked 

 their roots the Phylloxera became a new disease. 



Before we have been able to find a remedy for the old Potato 

 disease we are threatened with another — the Colorado beetle, 

 or American Potato bug as they call it. They call everything 

 a bug : the woolly aphis, another American production which 

 we could have very well dispensed with, they call the mealy 

 bug. This insect is called the Doryphora decemlineata. The 

 meaning of the first word is Sword-bearer, and of the last Ten- 

 lined, from the number of stripes on the body ; but I believe 

 these stripes have to be carefully examined to be able to count 

 the number. The eggs are deposited by the female to tha 

 number of about seven to twelve hundred at intervals during 

 forty days on the leaves of the Potato in somewhat irregularly 

 arranged clusters. In about six days they hatch into larva? 

 or grubs, and feed upon the foliage of the plants from seven- 

 teen to twenty days ; then they descend into the ground, and 

 after remaining in the pupa or mummy-like state to which the 

 larva change for ten or twelve days, they again make their 

 appearance as perfect beetles. In about a week the Bexes pair, 

 and in another week the females begin to lay their eggs ; henoe 

 it is oalculated that they can produce three broods per annum. 

 Mr. Townsend Glover, the United States entomologist, says 

 that if the progeny of a single pair were to be allowed to 

 increase without molestation for one season the result would 

 amount to over sixty millions. There are many other inter- 

 esting facts known about this beetle which have appeared in 

 various publications, but they need not be mentioned here. 



The Doryphora deoemlineata does not owe its origin to 

 spontaneous generation, neither did it suddenly arise in con- 

 sequence of any peculiar electrical Btate of the atmosphere. 

 It has fortunately long been known to naturalists, and was 

 discovered more than fifty years ago feeding on a plant called 

 Solanum rostratum, a poor relation of the edible Potato, grow- 

 ing on the eastern slope of the Rocky Mountains, and there 

 it would have rested until this day but for the gradual spread 

 of the emigrant and the cultivation of the Potato, which 

 afforded it the means to transfer itself from the uncultivated 

 to the cultivated flower, and from the wilds of the Rocky 

 Mountains to the cultivated plains, and from the eastern States 

 of America to the western States, and from the western States 

 to Canada, and from thence to Europe. 



We have now seen how a plant and various insects have 

 lately appeared in this country and on the Continent, and how 

 rapidly they have spread over it and the injury they have 



