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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



is essentially passive and due to a substance within the sporange wall 

 capable of swelling and so expelling the spores, aided by their connecting 

 axial filaments. This substance is even more clear in Achlya. [As the 

 sporangial wall is freely permeable to water, such a swelling substance might 

 expel the first spore but not the others ; as shown years ago, the swelling 

 substance, undemonstrable by any reagent, does not provide a mechanism 

 that accounts for the facts.] The spores, sausage- shaped on their escape, 

 round off and encyst in the well-known hollow-spherical aggregate, as in 

 Achlya, Hartog ascribes this to mutual attraction (" adelphotaxy ") in 

 Achlya, the species which he and Cornu [and all other observers save 

 * Rothert] examined being flagellate. But Aphanomyces clearly has no 

 flagella, any more than Rothert's Achlya. The aggregation must be due 

 to the connections by the plasmatic filaments and the viscid surface 

 of the spores and the pressure of the expulsive substance. [We have 

 never seen a hollow sphere formed in Aphanomyces, but a subspherical 

 solid heap of the encysted spores. If the plasmic connections were functional, 

 as they are diametrically opposite, the aggregate would be a string ; if the 

 viscid surface, the spores would form a mass of polyhedra, not of spheres.] 

 The zoospores escape shortly (say 2^ hours) after from the cyst in the 

 normal kidney shape with two flagella. " Cuttings " of Aphanomyces are 

 as useful as those of other Saprolegniece. — M. H. 



Apple Culture, Some Suggestions concerning (U.S.A. Exp. 

 Stn. Ohio, Bull. 137, Feb. 1903). — Some short but useful suggestions on 

 some of the most important questions w 7 hich have arisen under conditions 

 such as obtain in Ohio. The steady increase of destructive insects and 

 fungi has made a study of these forms of life necessary, and this has 

 resulted in great progress in methods of protecting the Apple crop, and 

 conservation of soil moisture has been proved to be of much importance 

 for the maintenance of fertility. As a site for an Apple orchard, elevated 

 ground is recommended, and fairly fertile clay loam is stated to be about 

 the best soil. Beech, Oak, and Chestnut lands are suitable for Apple 

 orchards, but not Elm land. As a result of experiment it has been found 

 that the trees should be planted from 25 to 40 feet apart, and no fillers 

 used, as they are likely to do more harm than good. Draining is essential 

 to the life and health of Apple trees, and, if not natural, it is best secured 

 with tile drains. Manuring, cultivation, and cover-crops are fully dealt 

 with. It is truly stated that so much has been said about the necessity 

 for spraying that there is danger of forgetting that trees need food as well 

 as medicine. It is advocated that during the first three or four seasons 

 Mime cultivated crop, such as Corn or Potatos, can be grown between the 

 trees to advantage. Wheat, Oats, Barley, Rye, or any sown crop, if 

 allowed to mature, deprives the soil of so much moisture as to affect the 

 trees injuriously, hence such crops should not be grown. 



On hilly ground, in fact wherever cultivation is difficult, and on soil 

 which washes, and where grass can be made to grow, the grass mulch 

 method is advised. Spraying is of course stated to be a matter of great 

 importance, and must go hand in hand with other essential operations. 

 Directions are given for making spraying mixtures, such as Bordeaux 

 mixture and ammoniacal solution of copper carbonate. — V. J. M. 



