AN ENCYCLOPEDIA OF HORTICULTURE. 



167 



Plain continued. 



of high excellence. Beginning and middle of September. One 

 of the most delicious Plums for dessert, and considered the finest 

 of the Gage tribe. Two seedlings have been raised by Mr. Rivers 

 from this variety, and named EARLY TRANSPARENT and LATE 

 TRANSPARENT GAGE. The first-named is said to ripen ten days 

 before, and the other ten days after, the typical sort. " The two 

 seedlings and the parent differ entirely in their growth, bnt are 

 almost identical in the quality and size of the fruit. The EARLY 

 TRANSPARENT is upright and compact, bnt vigorous ; the LATE 

 TRANSPARENT is dwarf and compressed" (Bavers). 



Victoria. Fruit large, roundish-oval, bright red, covered with a 

 thin bloom ; flesh very juicy and sweet. September. A well- 

 known and first-rate culinary Plum, very extensively cultivated 

 in market gardens, and worthy of a place in every collection. 

 The tree is a most abundant bearer, both as a standard and 

 against a wall 



Washington. Fruit large and handsome, deep yellow when 

 ripe, marked with crimson, and covered with pale bluish bloom ; 

 flesh firm, rich, and sugary. Middle of September. One of the 

 best culinary Plums, also sometimes used for dessert. 



White Magrmm Bonnm. Fruit very large, oval, deep yellow, 

 with thin, white bloom ; flesh firm, rather coarse, sub-acid. 

 September. A very large and valuable variety for cooking and 

 preserving ; it is usually known as the EGG PLUM. The tree is 

 vigorous, and generally bears well. 



Winesonr. Fruit rather small, oval, dark purple ; flesh juicy, 

 sub-acid. Middle of September. A very valuable variety for 

 preserving and for culinary purposes ; much esteemed in some 

 districts, but not so good in others. 



Woolston Black. Fruit medium, round, deep purple, with blue 

 bloom; flesh melting and richly flavoured, particularly after 

 becoming shrivelled. Beginning of September. Dessert. 



Of the Bnllace (Prunus insititia) there are several 

 varieties. The species grows wild in many parts of 

 Britain, and the fruits are much like Damsons, except that 

 they are round, instead of being oval. They are used for 

 cooking and preserving. The sorts best known are named 

 respectively BLACK, ESSEX, BOTAL, and WHITE. The 

 trees are usually enormous bearers. Amongst Damsons 

 the following are recommended: 



Fruit small, roundish-oval, dark purple or nearly 

 black. Middle and end of September. A well-known variety, 

 much esteemed for preserving. 



Crittenden's, or Cluster. Fruit larger than other varieties of 

 Damson, roundish-oval, black, with a thin bloom. Middle of 

 September. This is considered the best sort of Damson ; it was 

 raised in Kent, and has recently been brought into prominent 

 notice because of its extraordinary fertility. The tree forms a 

 handsome pyramid. 



Prune. Fruit oval, larger than the COMMON Damson, and con- 

 sidered better for preserving, but the tree is not generally so 

 productive. September. Much esteemed in the North. 



Rivers' Early. A seedling raised by Mr. Rivers from ST. 

 ETIENNE PLCM. Early in August, It is very early, and a valu- 

 able addition. 



White. Fruit oval, pale yellow, with a thin bloom ; flesh yellow, 

 agreeably acid. End of September. 



FUNGI. The Fungi parasitic on Plums need not be 

 greatly dilated upon, since few of them do much injury 

 to any part of the tree. A considerable number of 

 Pyrenomycetes have been found growing upon the dead 

 branches; but they are not known to be injurious to the 

 living plants, with a few exceptions mentioned below, 

 and even these are scarcely dangerous, except under 

 conditions that specially favour their growth. The leaves 

 are sometimes thinly covered with a white coating, com- 

 posed of filaments of the nature of those described under 

 Oidinm. After a time, there become visible, scat- 

 tered over this coating, small, round, black particles, 

 like grains of gunpowder. These, by the help of the 

 microscope, are seen to be perithecia, in each of which 

 is inclosed a single ascus, and in this lie eight colourless, 

 oblong, very minute spores, which escape by the walls 

 of the perithecium bursting when ripe. The latter body 

 is provided on the top with from three to seven upright, 

 stiff, slender outgrowths, each of which bifurcates four 

 or five times near the tip. This Fungus has received 

 the names Podosphcera Kunzei, and P. tridactyla. The 

 latter name is now generally adopted. Reproduction is 

 effected both by the spores described above, and by 

 means of conidia. developed as described under Oidinm. 



Plum continued. 



Though not uncommon, the Fungus is seldom very hurt- 

 ful to Plum-trees; but, where desirable to check its growth, 

 this may be effected by dusting the leaves with flowers 

 of sulphur, or by syringing them with a mixture pre- 

 pared from sulphur and quicklime, as recommended 

 under Mildew, or with potassium sulphide solution (see 

 Oidinm). 



Another Fungus parasitic on Plums, and named Eroascus 

 Pruni, gives rise to a peculiar condition of the fruit, 

 known as " Bladder Plums." The presence of this Fungus 

 is easily recognised by the great increase in the size of the 

 young fruits, as compared with healthy fruits of the same 

 age, by their elongated, pointed form, by the greyish-green 

 bloom on their surface, and by the diseased fruits being 

 hollow, like bladders, with frequently barely a vestige of 

 the seed. After a short time, these enlarged fruits turn 

 to a dirty -yellow colour, fade, and shrivel up. The 

 mycelium of this Fungus lives all the year round in the 

 soft bast of the twigs, which often show distinct traces 

 of its presence. From these it extends into the ovaries 

 of the flowers, along the woody bundles, and thence 

 spreads throughout the tissues, and comes to lie close 

 below the skin of the ovary. Branches grow out from 

 the mycelium, burst through the skin, and stand erect, 

 side by side, over the surface. Each reaches a length of 

 rather over jJoin., with a breadth of about a quarter 

 as much, and is supported on an oblong stalk-cell, about 

 one-fourth of its length, which rests on the surface of 

 the epidermis, not pressing between its cells. Each of 

 the longer cells is an ascus, and has inclosed in it eight 

 round spores, which are set free by the bursting of the 

 ascus, about the time the fruit withers. The spores are 

 scattered far and wide by the wind, and such as fall into 

 . favourable situations propagate the disease anew. The 

 ! only remedy likely to prove useful is to cut off, and burn 

 ! without delay, the fruits and branches that show traces 

 ! of the Fungus. 



The leaves of Plum-trees frequently show thickened, 

 fleshy, orange-red spots, of irregularly-rounded outline, 

 These are the work of a Fungus known as Polystigma 

 rubrutn. A section through one of these spots will 

 probably pass through one or more flask-shaped spaces, 

 some of which are perithecia, inclosing numerous asci, 

 in each of which are eight minute, oval, colourless spores. 

 Other of the flask-shaped bodies are pycnidia of the same 

 Fungus; and in them lie numerous slender, curved, rod- 

 like, colourless sporidia, each formed on the tip of a 

 small stalk. Both kinds of flasks have the walls in- 

 i separable from the surrounding tissues, and both open by 

 1 narrow mouths on the lower surface of the spots. On 

 ! examination, with the microscope, of a thin slice from 

 the leaf, the tissues are found crammed with the fila- 

 ! ments of the Fungus, and much altered. However, the 

 I spots are rarely so numerous as to do much harm to 

 j the leaves, though they take nourishment from them, 

 ! and prevent the proper fulfilment of their functions. 

 This Fungus is widely spread, in Europe, Asia, and North 

 America. Where the Fungus is doing harm to Plum- 

 trees, it will be well to collect and burn the diseased 

 leaves, and also those which have fallen. Sorauer recom- 

 mends digging the latter into the ground in early spring, 

 before the young leaves burst from the buds, to prevent 

 risk of their being infected. As regards the prevention 

 of diseases of Plum-trees, it is very desirable to remove 

 from their neighbourhood Sloe-bushes and Bird Cherries, 

 since the disease-producing insects and Fungi live on these 

 species as well as on the Plum. 



Plums frequently suffer badly from the action of Oidium 

 fructigenum, for a full account of which, including 

 remedies, see Pear (FUNGI). The Fungus sometimes 

 covers the entire surface of the fruits, rendering them 

 quite white, and causing them to dry up. 



INSECT PESTS. These are not very hurtful in the 



