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All these are puzzling structures; and there is another minute body within the cell, called the centro-some, that is quite as much so. This structure, discovered by Van Beneden, has been regarded as essential to cell division, yet some recent botanical studies seem to show that sometimes it is altogether wanting in a dividing cell.
Thus, Van Beneden, in his work on parasites, while classing female mosquitoes with his "miserable wretches," yet says, "If blood fails them, they live, like the males, on the juices of flowers." If this be so, it is quite certain that the juices fail to satisfy them; and that, like Dr.
The sixth and last section is devoted to Embryological systems, and presents diagrams of the classifications of Von Baer, Van Beneden, Koelliker, and Vogt. The second part of the Monograph introduces us to the consideration of a special subject of Natural History, the North American Testudinata.
The upper garment, or "rok," that is, the one above the waist, she called the "boven rok" and the lower one, beneath the waist, her "beneden rok." In Dutch "boven" means above and "beneden" means beneath. By and by, when, at the looms, more of the beautiful white linen was woven, she had a new petticoat made and put it on. She was so delighted with this one that she wanted more.
Thus they form long dense tufts in the males of many Diastylidae, as Van Beneden also states with regard to Bodotria, whilst the females only possess them more sparingly. In the Copepoda, Claus called attention to the difference of the sexes in this respect.
Numerous examples, which might easily be augmented, of such profound differences, are furnished by Leydig's 'Lehrbuch der Histologie. In the Crustacea the ovarian eggs actually sometimes furnish excellent characters for the discrimination of species of the same genus; thus, for example, in one Porcellana of this country they are blackish-green, in a second deep blood-red, and in a third dark yellow; and within the limits of the same order they present considerable differences in size, which, as Van Beneden and Claus have already pointed out, stands in intimate connexion with the subsequent mode of development.
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