690 ARTHROPODA SUB-KINGDOM VII 
Uroceridae (Wood Wasps), Cynipidae (Gall Flies), Ichnewmonidae (Fig. 1478), 
Braconidae, Chrysididae (Gold Wasps), Vespidae (Wasps), Apidae (Bees, Fig. 1474), 
Formicidae (Ants, Fig. 1475), ete. They are most abundant in amber, and in the 

Fic. 1473. Fic. 1474. Fic. 1475. 
Ichneumonites bellus, Heer. Mio- Xylocopa senilis, Heer.  Mio- Prionomyrmex longiceps, 
cene; Oeningen, Baden. %/y (after cene ; Oeningen, Baden. 1/; (after Mayr. Oligocene; Baltic 
Heer). Heer). amber. 2/; (after Mayr). 
fresh-water strata of Aix, Oeningen, and especially Radoboj and Florissant. A species 
of Myrmar, one of the minutest insects known, belonging to the parasitic Proctro- 
trupidae, has been found in Baltic amber. 
Range and Distribution of the Insecta. 
According to Scudder, about 2600 fossil insects had been described up to 1885, 
of which 155 were Palaeozoic species, 475 Mesozoic, and 1972 Tertiary. Since then 
these figures have been considerably increased by discoveries at Commentry, Florissant, 
in amber and elsewhere. 
The oldest fossil insect is Protocimex from the Swedish Ordovician. Following 
this are Palaeoblattina trom the Middle Silurian of Calvados, France, and several 
Devonian forms from New Brunswick. 
A marked increase in numbers and variety of form is observed in the Coal 
Measures, the most noted localities being Commentry in Department Allier, and 
Mazon Creek, Illinois. Other localities for the older fossil insects are Zweibriicken, 
Wettin-Lobejiin near Halle, Manebach in Thuringia, the Belgian and British coal- 
fields in Europe, and Nova Scotia, Pennsylvania, Ohio, and Rhode Island in America. 
The Permian (especially the Rothliegendes of Weissig in Saxony, Stockheim. in 
Bavaria, Lebach near Saarbriicken, and Cassville, West Virginia) yields few, but in 
part very interesting species, for example, those of Eugereon. From different localities 
of the Trias, Heer describes several Orthoptera, and also two beetles from Vaduz in 
Liechtenstein. To these must be added about twenty species recently discovered in 
the South Park of Colorado, nearly all of which are cockroaches. The Lias of 
Schambelen in Aargau, Dobbertin in Mecklenburg, and Gloucestershire, England, 
contains a tolerably rich insect fauna. Only a few species are derived from the 
Stonesfield Slates, but the Purbeck of Southern England, on the other hand, is quite 
rich. Excellently preserved remains are found in Lithographic Slates (Upper Jura) 
of Bavaria, especially at Solenhofen, Eichstiitt, and Kelheim. The Cretaceous again is 
very poor in insect remains, most of the forms occurring in Bohemia. 
Some Eocene species are known, but for the most part not yet fully described, — 
from the Isle of Wight and phosphorites of Querey, France. The Oligocene insect 
fauna is surprisingly rich and varied. By far the greatest number of species is 
derived from Baltic amber; other interesting localities are Aix in Provence, 
Florissant, and the White River region of Colorado. The Miocene localities of 

