Mi 



NOTES ON THE ORTHOPTERA (continued). 

 By M. P. Somes, Missouri State Fruit Experiment Station, Mountain Grove, 



The second great group of the Orthoptera, the Leaping Orthoptera, may be 

 divided into three families, as follows: 



Antennae much shorter than the body, relatively stout; tarsi or feet with 

 three joints; evipositor short and but slightly exserted .... The Locusts 

 (Acridiidae). 



Antennae much longer than the body, slender, delicately tapering; feet with 

 three or four joints; ovipositor commonly elongate, much exserted, either as a 

 compressed blade or needle-like. 



Tarsi or feet four jointed on all legs, or at least on the middle pair. 



Tegmina or front wings, with the sides sloping; ovipositor usually in the form 

 of a flattened blade, the tip not expanded. . . . The Green Grasshoppers 

 (Locustidae). 



Tarsi or feet three jointed, though not always alike in structure, on all the 

 pairs of legs; tegmina or front wings flattened above and with the sides bent 

 abruptly downward; ovipositor usually exserted, forming a cylindrical needle, with 

 the tip more or less expanded The Crickets (Grylhdae). 



These three families include by far the greater majority of our Orthoptera 

 and are all more or less familiar to every one. They include about eight hundred 

 species in the United States, of which number about sixty per cent belong to the 

 first family, the Acridiidae, with the Locustidae next in point of numbers and the 

 Gryllidae closing the list with relatively few species. 



The Acridiidae, or "Short-Horn Grasshoppers," as they are sometimes called, 

 are the true "Locusts," and at least in the United States include practically all 

 of the seriously injurious forms of Orthoptera. Indeed, the ravages of one species, 

 "The Rocky Mountain Locust," which belongs to this group, may be said to 

 have made entomological history in this country some years ago, although at 

 present this species is apparently extinct within our borders. The group is made 

 up, so far as forms in the United States are concerned, of four subfamilies. 



"The "Grouse Locusts" (Tettiginae) are small insects, half an inch or less 

 in length, with the upper portion or roof of the prothorax extended back, covering 

 all or nearly all the abdomen. They are usually grayish or blackish in color and 

 are usually found in moist, sandy places, many species being common along the 

 margins of streams. In most species the hind femora are greatly swollen, giving a 

 hint as to the truly surprising leaping powers possessed by these small locusts. 



The second subfamily, the Tryxahnae, has apparently no generally accepted 

 common name, though they are frequently spoken of as the "Tryxalids." They 

 commonly have an oblique head, slender form, with long slender legs, and the 

 hind wings are commonly clear and transparent. They are insects of moderate to 

 fairly large size, although some species are quite small. The dorsal portion of 

 the prothorax projects but slightly, if at all, over the extreme basal segments of the 

 abdomen. This subfamily is found most commonly in areas of rich, low vegeta- 

 tion, although some are to be found in fields and meadows, some in rocky places 

 and a few even as rather serious pests in cultivated fields. 



The third subfamily, the Oedipodinae, like the above, are not blessed with 

 any common name. For the most part they may be distinguished by the fact that 

 the hind wings are colored rather than transparent, the general field of the wing 



153 



