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Fossil Spiders.

Although no Spiders have been yet discovered in any rocks so ancient as the Carboniferous series, the presence of Insects in this series, and also of Scorpions, renders it highly probable that the cognate family of Spiders was coordinate with Scorpions, in restraining the Insect tribes of this early epoch, and that it will ere long be recognised among its fossil remains.*

The existence of Spiders in the Jurassic portion of the Secondary formations has been established, by Count Munter's discovery of two species in the lithographic limestone of Solenhofen. M. Marcel de Serres and Mr. Murchison have discovered fossil Spiders in Fresh-water Tertiary strata near Aix in Provence. (See Pl. 46", Fig. 12.)

* The animal found by Mr. W. Anstice in the Iron-stone of Coalbrook Dale, and noticed by Mr. Prestwich as "apparently a Spider" (Phil. Mag. May, 1834, v. iv. p.. 376,) has been subsequently laid open by me, and shown to be an Insect, belonging to the family of Curculionidæ. (Pl 46′′, Fig. 1.) At the time when it was figured, and supposed to be a Spider, its head and tail were covered by iron-stone, and its appearance much resembled an animal of this kind. Mr. Prestwich announces also the discovery, in the same formation, of a Coleopterous Insect, which will be farther described in our next section, as referable also to the Circulionidæ..

It is scarcely possible to ascertain the precise nature of the animals, rudely figured as Spiders and Insects on Coal slate by Lhwyd, (Ichnograph, Tab 4,) and copied by Parkinson, (Org. Rem. V. iii. Pl. 17, Figs. 3, 4, 5, 6;) but his opinion of them is rendered highly probable by the recent discoveries in Coalbrook Dale: "Scripsi olim suspicari me Araneorum quorundam icones, unà cum Lithophytis in Schisto Carbonaria observasse: hoc jam ulteriore experientiâ edoctus apertè assero. Alias icones habeo, quæ ad Scarabæorum genus quàm proximè accedunt. In posterum ergo non tantùm Lthophyta, sed et quædam Insecta in hoc lapide investigare conabimur." Lhwyd Epist. ii, ad fin..

Fossil Scorpions.

The address of my friend Count Sternberg to the members of the National Museum of Bohemia (Prague, 1835,) contains an account of his discovery of a fossil Scorpion in the ancient Coal formation at the village of Chomle, near Radnitz, on the S. W. of Prague. This most instructive fossil (the first of its kind yet noticed) was found in July, 1834, in a stone-quarry, on the outcrop of the Coal measures, near a spot where coal has been wrought since the sixteenth century. In the same quarry were found four erect trunks of trees, and numerous vegetable remains, of the same species that occur in the great Coal formation of England..

A series of drawings of this Scorpion was submitted to a select committee at the meeting of Naturalists and Physicians of Germany, in Stutgard, 1834; and from their report the subjoined particulars are taken.. All our Figures, (Pl. 45'.) are copied from those attached to this Report, in the Transactions of the Museum of Bohemia, April,. 1835.*

* This fossil Scorpion differs from existing species, less in general structure than in the position of the eyes. In the latter respect, it approaches nearest to the genus Androctonus, which, like it, has twelve eyes, but differently disposed from those of the fossil species. From the nearly circular arrangement of these organs in the latter animal, it has been ranged under a new genus, Cyclopthalmus.

The sockets of all these twelve eyes are perfectly preserved, (Pl. 46. fig.. 3.) One of the small eyes, and the left large eye, still retain their form," with the cornea preserved in a wrinkled state, and their interior filled with earth.

The jaws also are very distinct, but in a reversed position.. (Pl. 46'. fig.. 2. a.) Both these jaws have three projecting teeth, and one of them (Pl. 46', Figs. 4. 5.) exhibits, when magnified, the hairs with which its horny integument was covered.

The rings of the thorax, (apparently eight) and of the tail, are too much dislocated for their number to be accurately distinguished, but they differ from all known species. The view of the back (Pl. 46', Fig. 1.) has been. obtained by cutting into the stone from behind.

The under surface of the animal is well exposed in Fig..2, with its cha-

As far as we can argue from the analogy of living species, the presence of large Scorpions is a certain index of the warmth of the climate in which they lived; and this indication is in perfect harmony with those afforded by the tropical aspect of the vegetables with which the Scorpion, found in the Bohemian coal-field, is associated.

SECTION IV.

Fourth Class of Articulated Animals.

FOSSIL INSECTS.*

ALTHOUGH the numerical amount of living Insects forms. so vast a majority of the inhabitants of the present land, few traces of this large class of Articulated animals have yet been discovered in a fossil state. This may probably re-. sult from the circumstance, that the greatest portion of fossil animal remains are derived from the inhabitants of salt water,.

racteristic pincers on the right claw. Between this claw and the tail lies a fossil carbonized Seed, of a species common in the Coal formation.

The horny covering of this Scorpion is in a most extraordinary state of preservation, being neither decomposed nor carbonized. The peculiar substance (Chitine or Elytrine) of which, like the elytra of Beetles, it is probably composed, has resisted decomposition and mineralization. It can readily be stripped off, is elastic, translucent, and horny. It consists of two layers, both retaining their texture. The uppermost of these (Pl. 46', Fig. 6. a.) is harsh, almost opaque, of a dark-brown colour, and flexible; the under skin (Pl. 46', Fig. 6. b.) is tender, yellow, less) elastic, and organized like the upper. The structure of both exhibits, under the microscope, hexagonal cells, divided by strong partitions. Both are penetrated at intervals by pores, which are still open, each having a sunk areola, with a minute opening at its centre for the orifices of the trachea. Fig. 7. repre-' sents impressions of the muscular fibres connected with the movement of the legs.

* See Pl. 46′′. Figs. 1. 2. & 4.-11.

a medium in which only one or two species of Insects are now supposed to live.

Had no indications of Insects been discovered in a fossil state, the presence in any strata, of Scorpions or Spiders both belonging to families constructed to feed on Insects, would have afforded a strong à priori argument, in favour of the probability, of the contemporaneous existence of that very numerous class of animals, which now forms the prey of the Arachnidans. This probability has been recently confirmed by the discovery of two Coleoptera of the family Curculionidæ in the Iron-stone of Coalbrook Dale,* and also of the wing of a Corydalis, which will be noticed in our description of Pl. 46".

It is very interesting and important, to have discovered in the Coal formation fossil remains, which establish the existence of the great Insectivorous Class Arachnidans, at this early period. It is no less important to have found also in the same formation the remains of Insects, which may have formed their prey. Had neither of these discoveries been made, the abundance of Land plants would have implied the probable abundance of Insects, and this probability would have involved also that of the contemporaneous existence of Arachnidans, to control their undue increase. these probabilities are now reduced to certainty, and we are thus enabled to fill up what has hitherto appeared a blank in the history of animal life, from those very distant times when the Carboniferous strata were deposited.

All

The Estuary, or Fresh-water formation of those strata of the Corboniferous series which contain shells of Unio, in Coalbrook Dale, and in other Coal basins, renders the presence of Insects and Arachnidans in such strata, easy of explanation; they may have been drifted from adjacent

* Our figures (Pl. 46′′. Figs. 1. 2.) represent these fossils of their natural size. See description of this Plate for farther details respecting them.

310

INSECTS IN SECONDARY AND TERTIARY STRATA.

lands, by the same torrents that transported the terrestrial vegetables which have produced the beds of Coal.

The existence of the wing-covers of insects in the Secondary Series, in the Oolitic slate of Stonesfield, has been long known; these are all Coleopterous, and in the opinion of Mr. Curtis many of them approach most nearly to the Buprestis, a genus now most abundant in warm latitudes. (See Pl. 46". Figs. 4. 5. 6. 7. 8. 9. 10.*)

Count Munster has in his collection twenty-five species of fossil insects, found in the Jurassic Limestone of Solenhofen; among these are five species of the existing Family of Libellula, (See Pl. 1, Fig. 49,) a large Ranatra, and several Coleoptera.

Numerous fossil Insects have recently been discovered in the Tertiary Gypsum of Fresh-water formation at Aix, in Provence. M. Marcel de Serres speaks of sixty-two Genera, chiefly of the Orders Diptera, Hemiptera, and Coleoptera; and Mr. Curtis refers all the specimens he has seen from Aix to European forms, and most of them to existing Genera.† Insects occur also in the tertiary Brown coal of Orsberg on the Rhine.

* M. Aug. Odier has ascertained, that the Elytra and other parts of the horny covering of insects, contain the peculiar substance Chitine or Elytrine, which approaches nearly to the vegetable principle Lignine; these parts of insects burn without fusion, or swelling, like horn, and without the smell of animal matter; they also leave a Coal which retains their form.

M. Odier found that even the hairs of a Scarabæus nasicornis retained their form after burning, and therefore concludes that they are different from the hairs of vertebral animals. This circumstance explains the preservation of the hairs on the horny cover of the Bohemian Scorpion.

He ascertained also that the Sinews (Nervures) of Scarabæi, are composed of Chitine, and that the soft flexible laminæ of the shell of a crab, which remain after the separation of the Lime, also contain Chitine.

Cuvier observes, that the Integuments of Entomostracons, are rather horny than calcareous, and that in this respect they approximate to the nature of Insects and Arachnidans. See Zoological Journal. London, 1825, vol. i、 p. 101.

† See Edinburgh New Phil. Journ. Oct. 1829.

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