SUBPHYLUM III 



INSECTA 



15 



Thorax much abbreviated, legs similar, ivith spiirs ; no cerci or terebra. 

 mandibles, thoracic and abdominal legs. 



Larvae with 



The earliest uiidoubted traces of Lepidoptera aie fouiid in Jurassic strata of 

 England, Spain, Bavaria and Siberia, and comprise a nnniber of genera belonging to 

 tlie faniily Palaeontinidae. Phragmatoe- 

 cites (Fig. 1577), Eocicada (Fig. 1578), and 

 Prolystra Oppenheim are exaniples, these 

 forms being somewhat distantly allied to 

 the non-suctorial Limacodidäe of our own 

 day. Several modern families make their 

 appearance in the Tertiary, bnt are repre- 

 sented by relatively few species. The 

 total nnmber of Tertiary species is not 

 over 85, as against some 60,000 Eecent 

 butterflies and nioths. Among North 

 American exaniples may be mentioned the 

 foUowing from the Miocene lake beds of 

 Florissant, Colorado, all described by 

 Scudder : Prodryas persephone (Fig. 1579), 

 Barbarothea ßorissanti (Fig. 1580), Jwpiteria charon, Lithodryas styx, Nymphalites 

 obscurus, Prolibythea vagabunda, Psecadia mortuella, and Stolopsyche libytheoides. 

 From the same locality Gockerell has described Ghlorippe wilmattae and some other 

 species, including a well-preserved larval form known as Phylledestes vorax. 



Fig. 1579. 



Prodryas persephone Scudder. Miocene lake beds ; 

 Florissant, Colorado, i/j (after Scudder). 



Order 35. DIPTERA Linnaeus. (Flies). 



Terrestrial or amphibious Insects with highly specialised suctorial mouth parts. 

 Antennae either long and multiarticulate, or consisting of a limited number of similar 

 or dissimilar joints. Only the fore wings are prominent ; these are usually well developed, 



membranous, highly specialised, narroiv, with 



/ ^ few cross - veins, and longitudinal veins 



1^^ sparingly branched. Hind wings always 



^^^^Mp^^^^^E reduced to clubbed ßlaments, the so-called 



Fig. 1580. 



Bdi-barothea florismnti Scudder. 

 Miocene lake beds; Florissant, Colo- 

 rado. Vi (after Scudder). 



oTCU 



Fio. 1581. 



Architipula seehachiana Handl. Upper 

 Lias ; Dobbertin in Mecklenburg. 6/j (after 

 Ilandlirsch). 



" halteres." Thorax much abbreviated, legs generally homonomous, with five-jointed tarsi ; 

 abdomen without terebra or visible cerci. 



Upwards of 44,000 Recent and 1550 Tertiary species are known, 125 of the 

 latter being North American. The earliest Flies are found in the Upper Lias, and 

 comprise about 30 species, nearly all of which belong to the suborder Orthorrapha 

 of Brauer. They are grouped in the following named families : Protorhyphidae, 

 Mycetophylidae, Bibionidae, Psychodidae, Eoptychopteridae, Architipulidae (typified 

 by the genus Architipula Handl.) (Fig. 1581), Tipulidae and RhypÖidae. . In the 



