3144 



THE JOINTED ANIMALS 



in the tibiae of the fore-legs; and the chirping of the male is produced by the friction 

 of the wing covers over one another. The wing covers, instead of being both alike, 

 as in crickets, exhibit a certain amount of difference in the arrangement of the veins 

 and structure of the membrane in their basal part. Taking the male of the large 

 British green grasshopper as an example, it will be seen that on the portion of the 

 right elytron which folds horizontally over the trunk, there is near the base a some- 

 what irregularly circular area, which has a glistening appearance, like a piece of 

 talc. This area is bordered by a strong prominent vein. In a corresponding posi- 

 tion on the left elytron, which, when closed, overlaps the right, there are also some 

 thick transverse veins, but the cells inclosed by these veins have a similar texture 

 to the rest of the membrane. When the insect rubs its left elytron rapidly over the 

 right the veins projecting on the under side scrape on the margin of the mirror, and 

 set the latter in vibration, thus giving rise to the well-known sound. The chirp- 

 ing of the Lociistidce is generally louder and more prolonged than in the other 

 grasshoppers. In certain North-American species known as katydids, the song 



i. FEMALE OF Hetrodes spinulosus; 2. MALE AND FEMALE OF Meconema varium. 

 (All natural size.) 



seems to consist of these words repeated again and again, with a slight variation. 

 The life history of the Locustidce, so far as it is known, does not differ in any 

 essential respect from that of the Acridiidce. It is probable that in most cases the 

 female uses her long ovipositor to lay her eggs at some depth in the ground, though 

 in some species the female is known to deposit her eggs on plants. These grass- 

 hoppers are less herbivorous in their habits than those belonging to the next family; 

 many of them are, in fact, believed to be more carnivorous than herbivorous in 

 their tastes. The Locustidce are most numerous in species in America and Asia; 

 there being not many more than two hundred species in Europe, of which about 

 ten are British. In the large green grasshopper {Locusta viridissima) , which is 

 nearly an inch and a half long, and is easily distinguished by its size from all the 

 other British species, the male makes a harsh and strident noise, by which atten- 

 tion is attracted, when otherwise, owing to its green color, it might altogether 

 escape notice. Green is the prevailing tint in very many species of this family. 

 In some species the elytra have the most exquisite resemblance in color and 



