ARTHEOPODA — MILLIPEDES AND INSECTS. 105 



insects, notably the slight appeal which their crushed frag- Galle 

 ments make to entomologists, it has not as yet proved 

 possible to arrange an exhibited series in such a manner as 

 either to indicate the riches of the Museum or to give a 

 clear view of the palaeontological history of the Class. 

 Here then it can only be stated that, although the earlier 

 insects of Palaeozoic age have a primitive character, still 

 they can be connected with some of the Orders into which 

 modern insects are divided. Other of those Orders first 

 appear at a rather later date. The Orders are: 1. Aptera, 

 wingless insects, including the spring-tails, first found in 

 the Carboniferous 2. Orthoptera^ including cockroaches, 

 possibly from Silurian, certainly from Carboniferous onwards; 

 earwigs, beginning in Lias ; grasshoppers and the like, from 

 Lias onwards. 3. Neuroptera, including may-flies, dragon- 

 flies, caddis-flies, and white ants ; ancestral forms are found 

 as far back as the Devonian if not before ; more modern 

 types come in with the Mesozoic Era. 4. Hemiptera, 

 including bugs, plant-lice (Aphidae), scale insects, and 

 harvest flies ; an hemipterous wing is found in the Upper 

 Ordovician of Sweden, and more nearly complete fossils from 

 the Carboniferous onwards, while modern families come in 

 Mesozoic rocks. 5. Coleoptera or beetles are not certainly 

 known before the Triassic Epoch. 6. Diptera or flies are 

 first found in the Lias, but are neither numerous nor readily 

 identified before Tertiary times. 7. Lepidoptera, or butter- 

 flies and moths, are as yet known only from Tertiary strata. 

 8. Hymenoptera, including bees, wasps, ants, and gall-flies, 

 are represented by ants in the Lias, but are mostly found in 

 later Tertiary beds. 



In the British series, the Orthoptera of the Coal Table- 

 Measures include forms allied to cockroaches, among which 

 the specimens of EteoUattina (Fig. 52) and Le'ptoUattina 

 are noteworthy. Nodules of the same age contain wings of 

 the ^Qwco^iQx^ Lithosialis (Fig. 53 a), Brodiea, showing bands 

 of colour (Fig. 53 and Lithomantis with its expanded pro- 

 thorax (Fig. 54), formerly considered an ally of the recent 

 praying insect Mantis. The insects found in Liassic rocks 

 are for the most part small and insignificant, but there is a 

 moderate-sized dragon-fly, Lihellula, from both Lower and 

 Upper Lias, and from the Lower Lias of Barrow-on- Soar 

 near Leicester comes a ISTeuropteron allied to the white ants 

 and called Pcdaeotermes. Elytra of beetles, sometimes with 

 a metallic lustre, are common in the Stonesfield Slate, 



