we shall notice a minute dark dot corresponding to the oldest part of the oyster shell; it is, in fact, the oldest part of the starch grain. Around this point we can see as we focus up and down, ring after ring where the grain has grown larger and larger. The dark spot is called the hilum and the rings are known as striations. In the potato starch grain the hilum is not central and the striations are not circular. Wheat has large and almost round grains without a hilum or striations, those of Barley are very similar but smaller and not so uniformly round. Rye grains are frequently cracked and often have ragged edges. A very large number of these objects may be examined, for it is useful to know their structure if one’s object be to examine various foods; from the point of view of beauty, when examined with a polariscope, they have few rivals. Maize starch, which is to be found in most houses under the name of corn flour consists of two kinds of grain. Some are many sided and angular, all of one size and without striations, they are also split at the centre; the other grains are rounded, of various sizes and are never like the angular grains grouped together. The former come from the horny part of the maize, the latter from the floury portion. Rice starch is also many sided and angular, almost crystal like; there are, however, never any rounded forms and this serves to distinguish it from maize starch. The shape of Arrowroot starch grains varies according to the plant from which it is derived, for this substance does not all come from one kind of plant but, whether the grains be pear shaped, hammer shaped, triangular or dumbell shaped they all show striations and an x-shaped split in place of a hilum. Tapioca starch grains are usually grouped together in twos or threes; when they rest on their flat surfaces they appear circular and each hilum is surrounded by a dark ring, when on their sides they are seen to be sugar-loaf shaped. Many more starches can be found without going far afield, Sago, Peas, Beans, Lentils and Bananas are a few common commodities containing starch. An effort should be made to study the very curious dumbell shaped starch grains of the Spurge and its relations. All these plants contain a white milky juice in which the starch grains float; by squeezing a little of this milky fluid into a drop of water on a clean slide the grains can easily be observed. It is sometimes difficult to observe starch grains till a fair amount of experience has been gained in the use of the microscope. Should this difficulty arise, it may be overcome by adding a drop of a weak solution of iodine. This will stain the starch grains a deep blue colour and render them very easy of observation. The iodine solution must be weak, however, or the staining will be excessive and the objects rendered black and non-transparent.