Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/319

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SPIDEKS.] ARACHNIDA 299 protected by horny integuments, and often armed with spines to an extent that would make them a painful meal to any bird or other creature that should set itself to dine upon them. Phoroncidia Tkwaitesii (Cambr.), found in Ceylon, and Pycnacantha Meadii (Bl.), found in Africa, and indeed all the Gasteracanthides, are notable examples of this protective armature. Protective mimicry " is also seen in spiders, some so exactly resembling ants, that placed side by side with species of ants found in the same localities, even, a practised eyo would not detect the spider at first sight. Of this nature are the Myrmecide* (fig. 31) and some of the Saltici, and, notably, Aphantochilus Fio. 31. Ant-spider (Afyrmeciafuh-a, Latreille). , ccphalo-tliorax ; Z>, abdomen. Rogersii (Cambr.), found in Brazil. Other spiders, again (Genus Eiirysoma, Koch, and Cyrtarachnt. Thor.), closely resemble some species of phytophagous coleoptera one of the latter genus found in Ceylon, but yet undescribed, resembles a small mollusc. Of the former some are very like a minute crab (fig. 32). And lastly, to sum up the enemies of spiders, they prey on each other, and are preyed upon also by other Arachnids; but on the whole they have, as by their office they should have, the best of it, for they are against all the Articulata, but only comparatively a few of the Articulata are against them. Snulrr= -irn Tint rrpntiirps whiVh Fl<3 32. Crab-spider (Eurysoma opiaers aio not creatures icii ca bind^ capeiio). a, cepimio- belong solely to the present geo- thorax; b, abdomen, logic era of the earth, for fossil spiders, with other Arach nids, as well as spiders in amber, have been found; the oldest in the coal formation. See on this subject a late resume" by Dr T. Thorell, On European Sjnders, pp. 220- 233, with other works there quoted. PRESERVATION OF SPIDERS. Beautiful as are the col ours and markings of numbers of spiders, especially of those found in the tropics, and elegant and curious as are many of their forms and structures, it has yet been found a matter of difficulty to make them good-looking, sightly, cabinet objects. By ordinary care and skilful manipula tion, however, most of them can be preserved and dis played very satisfactorily. So much of the comparative neglect of Arachnids in general is owing to this difficulty, that it may perhaps be worth the space of a few lines to remark, that many whose abdominal integument is strong, or pretty thickly clothed with hairs and pubescence, may be pinned, set out, and dried like insects. - Others may have the abdomen opened from below, and after tho contents are carefully extracted, be stuffed with fine cotton wool. Others again have been most successfully treated by inflating the abdomen (after the contents have been pressed out) with a blow-pipe, and then subjecting them to a process of rapid desiccation, which in general preserves the colours and markings very well indeed. But the best and most useful way for all purposes is to immerse and keep them in tubes filled with spirit of wine. To make spiders in spirit sightly objects, they should, when drugged with chloroform, or some other stupifying agent, bo secured, but not transfixed, by pins to a piece of cork, sunk in a vessel of spirit, in a natural position, until ren dered rigid by the action of the spirit, which will be in a fortnight or so ; the pins are then removed, and the spiders are placed in glass test tubes, large enough to re ceive them without too much compression of the legs. A bit of white card is slipped in under the specimen to keep it Ih position, the tubes are filled with spirit, stopped firmly with a pledget of cotton wool, and inverted round tho inner side of a wide mouthed glass-stoppered bottle ; this bottle is filled also with spirit, and the spider is then seen in its natural position, and with all its colours and mark ings perfectly visible. It is also capable of examination with an ordinary pocket lens, even without removal of the tube from the large bottle. Large spiders with a largely developed abdomen should be kept in pill-boxes for a fort night or so before being placed in spirit; during this time the crudities of their food contents are discharged, and preservation without injury or obliteration of colours and markings is thus rendered far more certain ; the beauty of many of oui large and handsome epe irids can only be cer tainly retained, even in spirit, when treated after the above method. See further on this subject, as well as on the mode of search and capture of spiders (0. P. Cambridge, Trans. New Zeal Instil., vol. vi. pp. 194-200). It is not necessary to give here a list of works on Arachnids, many having been already quoted in speaking of the different orders. The following, however, on Ara- neidea may be mentioned: N. "VVestring, " Arancce sueacce, Gothenburg, 1861 ; E. Ohlert, Die Arancidcn odcr Echten Spinnen der Provinz Preussen, Leipzig, 1867; A. Menge, " Preussiche Spinnen," in Schr. Ges. Danz. (N. F.), 1866-1873, Danzig (still in course of publication); H. Lucas, in Exploration de I Algerie, Paris, 1849 ; H. Nicolet, in Gay s Hist. Fis. Pol. de Chili, vols. iii. iv., Paris, 1847 ; Eugene Simon, Les Arachnides de France (vol. i. only is yet published), Paris, 1874 ; L. Koch, Die Arachniden Australicns, Nuremberg, 1871-74 (still in continuation). Nothing has been said in the foregoing pages respecting the "Embryology" of spiders; for information in regard to this important and interesting but re condite part of Araneology, it must suffice to refer the reader to Herold, De Gcneratione Aranearum in Oro, Marburg, 1824, and Edouard Claparede, Recherches sur Devolution dcs Araignees, Utrecht, 1862. These, with other works quoted on the different points that have arisen in the course of the foregoing article, will be found sufficient to guide the student and collector. The general works on Arachnida, or on any of its separate orders, are exceedingly few, and none, except that of M. Simon, Hist, des Araignees, Paris, 1864, are of recent date, beyond the merest abstracts. The literature on the sub ject is scattered up and down, in isolated papers, in numberless Transactions and Proceedings of various socie ties, and in scores of periodical volumes and journals for the record of natural and scientific investigation. It has been attempted to give in the foregoing pages as fair a general view of the whole subject as the limited space, and great difficulty of getting access to important papers treating upon it, would permit. The object of such articles as the present is rather to excite an appetite for the obtaining more detailed information, than to satisfy fully

the appetite already excited. (o. p. c.)