The figure below (Fig. 46) shows a fossil also from the coal formations of Illinois, America, belonging to the family of the Euphoberiidae mentioned further on. It shows a nearer approach to the Julidae of the present time. The limbs, however, were of very curious shape, and may possibly have been adapted to locomotion in water as well as on land, and the small supposed branchiae on the ventral surface shown in Fig. 46, B, may possibly have been an arrangement to render respiration in the water possible. {74}In the secondary period the Myriapods were scantily represented, or, at any rate, geologists have failed to find their fossils. The class is represented by a single specimen found in the chalk in Greenland. This fossil, which has been included in the Julidae under the name of _Julopsis cretacea_, may perhaps belong to the Archipolypoda. Passing on to the Tertiary or Recent period, we find the Myriapods again numerous, and more nearly resembling those living at the present time. They belong mostly to the Chilognatha and Chilopoda. They have been found in the fresh-water gypsum of Provence in France, the brown coal of Germany, and the green river formations of America. Several have been found in amber. [Illustration: FIG. 46.—_Acantherpestes major._ (After Meek and Worth.) Mazon Creek, America. A, The whole animal; B, branchiae on the ventral surface.] Fossil Myriapods have been divided into four Orders, two of which coincide with the Orders of living Myriapods; the differences between the fossils and the living Myriapods having been held insufficient to warrant the establishment of a new Order. These two Orders are the Chilopoda and the Diplopoda or Chilognatha (Diplopoda is another name used by some writers for the group which we have hitherto called Chilognatha). The other two Orders have sufficient differences from living forms to render it necessary to include them in separate Orders. The fossil Myriapods, then, are arranged as follows:— Order I. Protosyngnatha. Order II. Chilopoda. Order III. Archipolypoda. Order IV. Chilognatha (or Diplopoda). The following table will show the species that have been discovered in the different strata:— Devonian, or } {75} Old Red Sandstone } 2 species of _Archipolypoda_ Carboniferous { 1 species _Protosyngnatha_ { 31 species _Archipolypoda_ Permian (Rothliegendes of Germany), 4 specimens belonging to the _Julidae_ or _Archipolypoda_. Cretaceous, 1 species { _Archipolypoda_ or { _Chilognatha_ Oligocene { 17 species _Chilopoda_ { { 23 species { _Diplopoda_ { (_Chilognatha_) Miocene, 1 species { _Diplopoda_ { (_Chilognatha_) I will now give a short account of the different Orders, and the fossil forms which are included in them. ORDER I. PROTOSYNGNATHA.