SUBPHYLÜM III 



INSECTA 



^99 



of crickets are known froni the Green Eiver Ecoene of Wyoming, and 

 are found also, witli locusts, in the Miocene lacustrine beds of 

 Florissant, Colorado. Various European species are known of J)ry- 

 madusa Stein. (Fig. 1539), and Gr ij II tis lAiui. (Fig. 1540). _ 



Fig. 1539. 

 Dryiriadusa sjteciosa (Heer). Miocene ; Oeiiingen, Baden, -/i 



Suborder B. ACRIDIOIDEA Handlirsch. 



Fig. 1540. 



Gryllus macrocercus 

 Germar. Lower Oli- 

 gocene; Baltic 

 amber. s/g (after 

 Germar). 



(Grasslioppers). 



Stridulating organs situated in the hind femora and a modified longitudinal vein of 

 the fore wings. Äuditory organ on the side of the ßrst abdominal segment. Antennae 

 short, composed of less than thirty Segments. Tarsi short, three-jointed. No exserted 

 ovipo'sitor in the female. 



Fig. 1541. * 



Tyrbula russelli Seudder. Miocene lake 

 beds ; Florissant, Colorado, s/g (after 

 Seudder). 



Tills is a group of com- 

 paratively late origin, and is 

 derived in all probability from 

 the Locnstopsidae or siniilar 

 lociistoid ancestors. Grass- 

 hüp})crs are known from the 

 Green Kiver Eocene of Wyom- 

 ing, and from the freshwater 

 Miocene of Florissant, Colorado, 

 and elsewliere. Tyrhula (Fig. 

 1541) and Nanthacia Seudder, 

 etc., are examples. 



Fig. 1542. 



Chresmoda obscura Germar. Tjithographic Stone (Upper Jura) ; 

 Solenhofen, Bavaria. -i/g (after Handlirsch). 



Order 6. PHASMOIDEA Leach. (Walking-sticks, Leaf Insects, etc.) 



Body usually long and slender, mouth parts orthopteroid, fore wings rarely well 

 developed, loithout stridulating organ, and without visihle demarcation hetween the 

 cubital and anal areas. Hind wings loith large, folded anal lohe; hind legs not 

 saltatorial, usually long and elender like the other pairs. Gerd short, genital appendages 

 of the female not prominent, tarsi five-jointed. 



Here is placed the Upper Jurassic genus Chresmoda Germar (Fig. 1542), which, 



