The characters which readily distinguish the Yellow Egg group are,—the large size of the fruit, possibly surpassing all other plums in size, the long-oval shape, more or less necked, yellow or purple color and the yellow flesh. The plums are produced on tall, upright-spreading trees. _The Imperatrice Plums._—This is a poorly defined assemblage of varieties, of which dark blue color, heavy bloom, medium size and oval shape are the chief characters. It is impossible to trace the origin of the group or to refer varieties to it with accuracy. The Imperatrice, of which Ickworth is an offspring, seems to have been one of the first of the blue plums to receive general recognition, and can as well as any other variety give name to the type. This group contains by far the greatest number of varieties of any of the divisions as here outlined, chiefly because the color, the size, and the shape are all popular with growers and consumers. This has not always been the case, for in the old pomologies, blue plums are comparatively few in number, Parkinson, for instance, giving in his list of sixty in 1629 not more than a half-dozen Domesticas that are blue. Among the varieties that fall into this group are:—Ickworth, Diamond, Arch Duke, Monarch, Englebert, Shipper, Arctic, Smith Orleans and Quackenboss. About the only characters that will hold for this large and variable group are those of the fruits as given above, though to these may be added for most of the varieties included in the division, thick skin and firm flesh, clinging stones and poor quality. The trees vary much but are usually hardy, thrifty and productive, making the members of the group prime favorites with commercial fruit-growers. _The Lombard Plums._—Just as the blue plums have been thrown in the last named group, so we may roughly classify a number of red or reddish or mottled varieties in one group. If the oldest name applicable to this group were given it should be called after the Diaper plums, well-known and much cultivated French sorts of two and three centuries ago. Since they are no longer cultivated, and as the Lombard seems to be a direct offspring of them and is fairly typical of the division, the name chosen is as applicable as any. These plums differ but little from those of the preceding group, except in color and in having a more obovate shape, a more marked suture, smaller size and possibly even greater hardiness and productiveness, and if anything, even poorer quality, though to this last statement there are several marked exceptions. In this group are no doubt many varieties which are crosses between some of the old red plums and varieties of the other groups given. The following sorts may be named as belonging here:—Lombard, Bradshaw, Victoria, Pond, Duane, Autumn Compote, Belle, Middleburg and Field. =2.= =PRUNUS INSITITIA= Linnaeus [Illustration: _PRUNUS INSITITIA_]