ORTHOPTERA. 193 



continent. It is of variable colors, ranging from dark brown to a dirty white above, 

 and blackish beneath. The pronotum, which is comparatively smooth and marked 

 with faint longitudinal strite, extends beyond the end of the body. Tettigidea poly^ 

 morpha, which differs from the preceding species in having the pronotum as short or 

 shorter than the body, has a like distribution, but is by far the more common species 

 of the two. 



Batrachidea differs from both Tettix and Tettigidea in having a more robust form, 

 and in possessing a prominent carina or ridge extending along the middle of the pro- 

 notum. Batrachidea cristata, in which the carina is very prominent and regularly 

 arched, is found throughout the eastern half of the United States, where it is chiefly 

 confined to timbered regions. This species is gray, and often very beautifully mottled 

 or marbled with various shades of brown and violet. 



Intermediate between this group, and closely connecting it with the balance of the 

 Aorididse, is a large, clumsy species, Phrynotettix verructdata, which is confined to 

 the southwestern portion of the United States, where it lives along streams. This 

 peculiar-looking locust measures about an inch and an eighth in length, and almost half 

 as much in width, and is variably mottled with gray, brown, and black colors. 



Throughout the southern portion of North America are found several very large 

 and clumsy-looking locusts, which bfelong to the genus Dictyophorus of Brulle and 

 Rliomalea of Burmeister. These insects have the elytra and wings shorter than the 

 abdomen, the antennae acuminate and somewhat flattened, and the vertex of the head 

 pyramidal. Dictyophorus centurio, which is yellow and black, is confined chiefly to 

 Florida and the adjoining portions of Alabama and Georgia, while Dictyophorus marci, 

 which is almost entirely black, enjoys a much wider distribution. Both species meas- 

 ure about two and one-half inches in length. 



The gigantic lobe-crested locusts of Central and South America, which are among 

 the largest of insects, and some of which have a wing expanse of from eight to nine 

 inches, live, as a rule, on bushes and trees. Tropidacris dux, which has the hind-wings 

 brick-i-ed, broadly margined with black, extends in its range from Panama to Texas. 

 Tropidacris rex, which is a closely allied species, is said to occur in Equador, while 

 both Tropidacris latreillei and T. fabricii are from Brazil. T. cristata is mentioned 

 as inhabiting Asia and Africa, as well as South America. This last species is some- 

 what smaller, and has the hind-wings pale greenish-blue, margined and mottled with 

 black, as in the preceding species. Titanacris carinata, a West Indian species, differs 

 from all of those belonging to the last named genus in the wings being immaculate. 

 Titanacris albipes is somewhat smaller, has a green band running from the apex to the 

 base of the wings, and has the lobes of the pronotum round and smooth. In the genus 

 Lophacris, of which there are three species, the wings are short, broad, and immacu- 

 late. Lophacris olfersii is cited as occurring both in China and South America, while 

 Lophacris velasquezii is from Vera Cruz, Mexico. Lophacris humholdtii differs from 

 both of the preceding species in having the hind-wings pea-green instead of red. It 

 is found on the west coast of South America. 



The genus Acridium, to which some of our most common North American locusts 

 belong, is a very extensive one, the species being mostly of large size, and including 

 several that are migratory and destructive to vegetation. Like the crested giants just 

 noticed, the species of Acridium are also inclined to be more or less arboreal in their 

 habits. The different species are found throughout all countries that lie within the 

 torrid and temperate zones. Acridium perigrinum is one of the true migratory 



VOL. II. — 13 



