Miscellaneous. 69 and habits of Limulus throw much light on the probable anatomy and habits of Trilobites. The author infers that the eyes had a similar structure, that the circulation and the nervous system were alike, and that probably the genital organs were very similar in the two groiips. He thence suggests that the eggs of the Trilobite were probably laid in the sand or mud and impregnated by the sperm-cells of the male floating freely in the water. The Trilobites probably lived by burrowing in the mud and sand, digging in the shallow palaeozoic waters after worms and stationary soft-bodied Inverte-brates. — The American Chemist, Nov. 1870. On the Stijmles of Magnolia and Liriodendron. By TnoMAS Meehan. An examination of the stipules of Maf/nolia affords some highly interesting facts, most or perhaps all of which are known to leading botanists, but which do not appear to be as generally known as they deserve to be ; and these facts may have a more intimate bearing on many of the questions connected with the laws of development than is suspected. In most species of Magnolia a scar peculiar to the genus exists on the petiole. This scar is elevated somewhat above the surrounding tissue, as if the matter forming it had been laid on the surface after the rest of the petiole had been formed. The green is not of the same tint as in the rest of the petiole, but it is always of the same tint as that of the leaf-blade. In Magnolia macroplujlla the petiole and under surface of the leaf are grey ; the leaf-blade is pale green on the upper surface. The surface of the scar is pale green, corresponding to the surface of the leaf-blade. The whole appearance of the scar is such as if a portion of a leaf-blade had been grafted by its under surface on the petiole. On the upper part of the scar next the leaf-blade are two small articulation points, where the membranaceous stipules finally parted from the leaf. Examining a leaf before these stipules have fallen, the main veins forming the skeleton of the stipules are found con-necting with these articuli, and, spreading out, divei'ge downward toward the base of the leaf. In separating at maturity from the petiole, they part first from the base, and last from their place of articulation. Their weakest hold is the point furthest away from what thus appears to be their source at the apex of the scar. Magnolia Frazeri elongates its petiole beyond the stipule several inches generally. The leaf-blade then exhibits the auricle so well known in this species. The structure of this auricle is similar to the stipules in M. macrophglla or M. tripetcda. The veins start out in nearly as close a fascicle as in these stipules, and they diverge and curve downwards just as these stipules do. Above these strong veins of the auricle are very weak veins, necessitating a very narrow blade })ortion there, until another set of strong veins push out and make the main part of the lamina. If we press these auricles back against the petiole, and imagine a
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