It is not by any means an easy task following Mr Stevens in the train of reasoning by which he evolves a Potato fungus from a Potato beetle, and associates it with Huxley and Tyndall, and the "bacteria," "all of a heap;" and it is really a relief to the reader to get quite lost and confounded with the lecturer, in a maze of Parliamentary evidence and much irrelevant matter that does not appear to have any earthly relation whatever to the subject of the lecture. Burns talked of "stringing blethers in a rhyme," but Mr Stevens's were strung to such good purpose, that one of his audience declared that, "for his part, he did not know that he was a bit wiser; but by groping in the dark," in the way they had begun presumably, he thought " they might stumble on something that would be a preventive or palliative of the disease." Considering that the lecturer had just traversed the field of science for more than two hundred years back, in order to make the beetle-fungus theory clear, such a remark was neither kind nor complimentary.

This was not all, however, for Mr Stevens's discovery got into the 'Scotsman;' and the lecturer being questioned regarding the "entomological" descent of the Peronospora infestans - secoud cousin to the Gooseberry caterpillar - he explained that the insect-view of the subject was adopted purely for the purpose of carrying the idea home to the minds of men, into whose heads it could not be beaten in any other way; "he therefore wrote for them [the East Lothian farmers] in such words as would carry the idea into their minds." The testimony of one of his listeners, already given, shows, however, that the lecturer's laudable object failed somewhat in this respect. It seems exceedingly probable that Mr Stevens's hearers went away with about as accurate an idea of the Potato disease "monster" in their minds, as the Irishman had of the mosquito after hearing a description of it, and recognised his entomological acquaintance in an elephant which he met soon after, exclaiming, "By jabers, if there ain't the very baste itself !" Mr Stevens's attempt to get out of the "entomological" situation, by throwing the blame on the stupidity of the class he lives amongst and associates with, is not generous, and cannot be accepted as quite satisfactory.

The whole tenor of the address, and the remarks that passed, show that the ignorance was not all on the side of the audience; and besides, Mr Stevens uses terms such as "bacteria," "mycelium," flocculent films, "zoospores," etc, without explaining them, that leads one to think he entertained a very high idea indeed of the intelligence of his hearers. In his closing remarks, he states that it is his "earnest desire that more and abler minds than his may give the subject consideration," - a sentiment to which we are sure any intelligent reader who reads his address will cordially subscribe.

Mr Luckhurst has been writing on the Potato disease in the ' Journal of Horticulture,' and although his arguments on that head are not very much to the point, he has one fact to record which is worth more than all the rest. He says he only secures his Potato crop when he lifts the tubers before they have finished their growth, and before the disease attacks them. His theory seems to be, that the disease does not manifest itself before maturation sets in, and if the Potatoes are lifted and stored before that period they will be saved; and he could, for years back, and does now, point to "store-sheds full of sound Potatoes " in proof of his statements. It is not the first time that early lifting has been suggested, if not practised; but whether the experiment has been fully tried or not, we cannot say. Mr Luckhurst will have done good service, however, if he can prove what he says in a perfectly satisfactory manner. If he has saved his crops on all occasions by the means he states, there is no reason why others should not do the same; and it is to be hoped the subject will receive further attention. We attach great value to statements like Mr Luckhurst's, but it is essential that they should be verified in the most satisfactory manner.

It appears that Mr Luckhurst lets his crops grow as long as he thinks safe; and as soon as the tubers have reached a fair size, and before a speck of disease appears on the foliage, he lifts and stores at once. What about the keeping qualities of the tubers stored at this stage ?

It has been stated by several correspondents of the 'Garden' that the Blue African Lily is hardy, or nearly so, in some parts of England, and succeeds well out-of-doors. For whatever purpose it is used it is a beautiful plant, and is well worth cultivating as a conservatory specimen, or for indoor decoration. Its tall spikes of delicate blue flowers render it a conspicuous and pleasing object anywhere. Its near neighbour, the Imantophyllum, is also tolerably hardy, and has been planted out and flowered well in the open beds in Yorkshire during the summer months. There are several varieties of this plant, the best producing very large trusses of deep orange-coloured flowers. We saw an immense plant of this in the front hall of a gentleman's house sometime since, and thought it one of the finest decorative specimens we had ever seen.

If it could be proved that the climate of Derbyshire and Yorkshire was superior to the climate of "Worcester, Hereford, and Kent," it may be readily comprehended that that interesting "under-ground" theory promulgated under the auspices of the Scottish Horticultural Association need not be quite abandoned. If Apples and Pears, etc, succeed better in a bad climate than in a good one, it is manifest that there must be something in the " stratum of soil" that does it. If, however, this question of climate cannot be sustained, we do not see what course is open to the able author of the 'Fruit and Flower Producing Agencies of Fibry Roots' but to capitulate as gracefully as he can; and the closing paragraph of a late communication of his to this paper shows how well he understands the amenities of polite discussion, and that this is not too much to expect from him. With regard to the question at issue - climate - here is what any one may read in any authentic topographical and statistical history of Worcester from which our author hails, - and the other two counties are much the same : "The soil of Worcester consists of almost every variety suitable for vegetation; its timber is magnificent, especially the Elm, which is called "the weed of Worcester. It produces table-fruit and vegetables of the finest quality, and its fertility has long gained for it the reputation of being the garden of the mid-west. The climate is mild and healthy, and the rainfall is nearly the minimum of England. Hopgardens are plentiful in the western division, and their produce ranks next to that of Kent." So much for Worcester.

Yorkshire, we learn from the same source, suffers from its inclination to the German Ocean; and as for Derby, we are told that it is " more a manufacturing and mining than an agricultural county," and that "the climate is cold and moist, with fogs and often frosts in summer." History does not make any allusion to the culture of hops in Derby or York, or to the manufacture of either cider or perry. The above description of "Worcester applied, we must remind the reader, five years ago; but the author of 'Fibry Roots,' etc, went there about that period, and the climate changed for the worse immediately, and it is now neither "early, dry, nor warm." What changes of a physical or other nature have happened there during these five years have not yet been chronicled, but a paper on that subject will, it is to be hoped, be forthcoming soon. The writer of the paper under review was "suddenly called to Edinburgh," and broke his journey at Leeds and Derby, where he spent probably about four-and-twenty hours, a good portion of the time in bed no doubt, and he had therefore "an opportunity of making climatical notes," hence his authority for his statements, which we do not of course attempt to controvert.

In taking leave of this subject, "Reader" has only to observe, that in criticising lectures or papers addressed to the whole world, he does not consider it incumbent upon him to put any other construction upon the words and phrases they may contain than these express and are meant to convey, and as they are evidently understood by those to whom they are addressed.

Reader.