Insects 1 59 



rather pale reddish, with a white line down the middle of the 

 thorax; the wings are without dark markings, but suffused with 

 yellowish-red, the pterostigma also being of this color. This 

 very distinct-looking species falls in the subgenus Belonia of 

 Kirby, a group of the Central American highlands, with one 

 species extending up the Rocky Mountain chain. The genus 

 Tramea includes some large strong-flying species. T. onusta of 

 Hagen, which Mr. E. Bethel has taken at Denver, has the broad 

 base of the hind wings brownish-black, the wings being other- 

 wise clear, with a short pale orange-brown stigma. There are 

 large light areas on the abdomen. This is a widely distributed 

 dragon-fly, extending to Central America and Cuba; it represents 

 an extension of a tropical group into the Rocky Mountain country. 

 The genus Sympetrum consists of modern sized species, the 

 wings usually about 25 to 30 mm. long. Some of the forms have 

 the basal half of the wings rust color or pale reddish, in others 

 the wings are quite clear. A female of S. corruptum was taken on 

 Arapahoe Peak (13,000 ft.) by Mr. E. Bethel in 1914, and Dr. 

 Calvert remarked at the time that this was probably the highest 

 recorded altitude for any dragon-fly in the world. S. danae of 

 Sulzer (scoticum of Donovan), determined by Dr. Calvert, was 

 taken by Mr. Hite at Gresham Lake in Boulder County, Septem- 

 ber 1907. This species extends all around the world in northern 

 regions, and is common in the British Islands. 



HEMIPTERA 

 The order Hemiptera, or Plant-bugs and their relatives, is 

 divided into two suborders. In the Heteroptera the upper wings 

 are largely more or less hard and opaque, like the elytron of a 

 beetle, but the apical part is membranous. In the Homoptera 

 the upper wings are of the same consistency throughout. All 

 have sucking mouth parts, except that adult male Coccidae have 

 no mouth; and the metamorphosis is incomplete, though approach- 

 ing the complete type in male Coccidae. Although the Coccidae 

 or scale insects seem to approach in their transformations the 

 series of higher insects which Imms calls Endopterygota,* they 

 are in fact a specialized group, leading to nothing beyond. 



The Endopterygota, or Holometabola, include such insects as the Lepidoptera, Hyme- 

 noptera, Diptera, Coleoptera, etc., which have a definite pupa stage. They are the "higher , 

 or more specialized insects. But Mecoptera and Neuroptera date back to Permian times, 

 and are thus of vast antiquity. Tillyard has even described (1924) Permian beetles from 

 Australia. 



