. La cyclopaedia d'anatomie et physiologie. Anatomie ; physiologie ; Zoologie. ARACIINIDA. •211 la vanne de certains organes d'une structure singulière qui s'appellent des peignes, pcctines, (Jig. 84, d), en raison de la disposition d'une série de petits appendices dont elles sont formées, et qui sont disposés sur la surface inférieure, l'un à côté de l'autre, comme les dents d'un peigne. Beaucoup de spéculations ont été offerts sur leurs utilisations. De nombreux naturalistes estiment qu'ils rendent l'assistance dans l'acte d'impregna- tion. Certains suppose qu'ils sont étendus au cours de la progression, et empêcher l'abdomen de th

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. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. ARACIINIDA. •211 the valve certain organs of a singular structure which are called combs, pcctines, (Jig. 84, d, ) on account of the disposition of a series of small appendages of which they are formed, and which are arranged on the lower surface one beside the other, like the teeth of a comb. Many speculations have been offered respecting their uses. Many naturalists believe that they render some assistance in the act of impregna- tion. Some suppose that they are extended during progression, and prevent the abdomen of the scorpion from trailing on the ground : others, again, regard them as hygrometrical organs, by means of which the animal judges of the humidity of the atmosphere. These are, however, all mere gratuitous hypotheses un- supported by any observation ; and the fact is that we have yet to learn the use of these pec- tinated appendages. Of the female generative system.—It has been long known that the orifices of the gene- rative organs in female spiders are situated at the base of the abdomen. We observe on that part of the body two distinct cavities, (Jig. 103, a, a, J which are closed by opercular pieces of Fig. 103.. a more or less solid texture, and it is at this part that the oviducts terminate. In the tege- naria domestica, these oviducts (b, bj are con- tinued internally in an insensible manner with the ovaries, which consist of a kind of bags (c, c) situated on each side of the intestinal canal, and to whose parietes the ova are attach- ed in a racemose manner. In the epelra diadema the ovaries are divided by two longitudinal membranous septa, and each is again subdivided by a transverse septum. The longitudinal sep- tum has no orifice, but the transverse one is perforated. There is, therefore, no communi- cation between the principal chambers of each of these ovaries, but there is a passage from the anterior to the posterior division, and the ova which are in the former

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