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In Mr. Lewis G. Mills's very interesting paper on the spiracles of the fly, in Science Gossip for September, he remarks—"The head of the fly contains the compound eyes with which it sees." This sentence revived a thought that I have often had before, and for which I am indebted to Mr. Walker for bringing into existence; namely—Is this wonderful compound structure an organ of sight? I presume that all readers of Science Gossip are familiar with the polygonal facets, and the fine hairs springing from between, which form the so-called compound eyes of insects; and I think all who have given the subject any attention will allow that these organs seem singularly unadapted for vision. An excellent idea of the incompatibility of an organ so constructed for the purpose of sight may be obtained by looking in a subdivided convex mirror, in which it will be seen that objects reflected are broken into confused distorted masses. Cuvier, speaking on this subject, says that the structure is so very different from that of other animals, that it would be difficult to believe it an organ of sight, had not experiments demonstrated its use. The experiments referred to were covering the compound eyes of a dragon-fly, which was then found to dash against objects in its flight, with every appearance of blindness. A wasp was treated in the same manner, and it ascended perpendicularly in the air, until it completely disappeared. Upon the simple eyes being covered also, it did not attempt to fly, but remained immovable. "How futile these arguments are," says Walker, in his admirable work upon the nervous system, "need scarcely be pointed out. The same results would occur if these were organs of touch, equally essential to the guidance of insects." Another fact pointed out by Walker tends to overthrow the theory of these compound structures being organs of vision, which is, that the black coat (pigmentum nigrum) is external to what may be termed the retina. The Gossiper in science will the better understand this by the following simple experiment:—Let him open the window of his room and hold the crown of his hat (if a black one) parallel to the glass on the outside; he will then find that, looking at the crown of his hat through the pane, his face will be reflected. This is a simple illustration of the action of the human eye. The hat represents the dark pigment, the glass the retina, and the man the object looked at. Now, in the so-called compound eyes of insects, the dark pigment is before, instead of behind the retina, and hence, as Walker observes, "comparative anatomists complain lamentably of the difficulty of understanding how, under such circumstances, vision can take place." From these and other circumstances, Walker hardly admits of a doubt but that the so-called compound eyes of insects are organs of touch. He says—"Is not, then, the white matter, well supplied with nerves, in these eyes, analogous to a portion of the true skin of the higher animals; the black matter, to the mucous net-work, which is dark in the negro, whose sensibility is greatest; and the exterior substance to the cuticle, in itself insensible even in man, and horny in insects, because their general surface is more or less so, but furnished with fine hairs, which in them are separated and supported by the hexagonal facets, and descend through the black substance to the true skin and its nervous fibrils." The hairs arising from between the facets may be compared to the whiskers of the cat, the extreme sensibility of which is well known. A very simple experiment, that I have often tried, tends, I think, to prove that the so-called compound eyes are organs of touch. Let the reader stand by his window until a fly settles on the outside of the glass, and then let him move his hand about over the inside, being careful not to cause any vibration, and it will be found that the fly will not be disturbed. The reason of this is obvious, if we allow the compound eyes to be organs of touch, the simple eyes being placed on the top of the head (as in the bee),—the interior of the room is hidden from the creature's sight, and the intervening glass destroys the exquisite sense of touch, that would otherwise give it warning of the approach of our hand.

If this should be the means of causing those better adapted than myself to give their attention to this interesting question, my end will be attained.

In an early number of Science Gossip I made a few remarks upon the varieties of British plants which had come under my notice. As the present year has enabled me to make several additions to my list, I may perhaps be allowed a short space in which to record my observations, promising that they have all been made in the neighbourhood of High Wycombe, Bucks.

The Wood Anemone (Anemone nemorosa) varies greatly in the number of its sepals; I have found specimens with five, six, seven, and eight respectively. Perhaps the most curious malformation which I have noticed is one in the Corn Poppy (Papaver Rhœas), which occurred in a corn-field near West Wycombe. The specimen alluded to had a persistent calyx, formed of four sepals, two of which were opposite at the base of the petals, and the other two at short distances down the stalk; all were much larger than is usually the case, and the upper two seemed part sepal and part petal, as they were streaked with red, and in some