THE TORTOISE BEETLES. 261 



which has not yet been named, and wliicli conies from Dorey, is 

 black, with a yellow belt; while another, also unnamed, is yellow, 

 with a large oval patch of black on the middle of the elytra, 

 and a round spot on the shoulder. Some species, again, are 

 yellow, with a blue band across the middle of the elytra. Amid 

 all the variety of colouring, the reader will see that yellow is 

 the hue which most prevails throughout the genus. 



The last family of these Beetles is called Cassidiidte. This 

 name is taken from the Latin word Cassida, which signifies " an 

 iron cap," and is given to the Beetles because their shape closely 

 resembles that of the basin-like steel cap which has been in and 

 out of fashion so often. Don Quixote's celebrated Helmet of 

 Mambrino really did bear some resemblance to the peculiar head- 

 covering called Cassida. 



We have but one genus of Cassidiidse in England, namely, the 

 well-known Tortoise Beetles, all belonging to the single genus 

 Cassida. These derive their popular name from the tortoise-like 

 appearance of the body, the resemblance between the insect and 

 the reptile being so close as to be at once apparent. Indeed, 

 suppose that anyone who was wholly ignorant of entomology 

 were shown a number of insects and asked to pick out the 

 Tortoise Beetles, he would do so wiLliout ever having seen a 

 Cassida before. 



None of our species are remarkable for beauty, their colour 

 being mostly a dull, pale green, which renders them almost in- 

 visible when they are clinging, according to their custom, to the 

 surface of some leaf. It is true that one or two species have 

 golden stripes on their elytra, but this colour fades after death 

 even more completely than the green, which, when the insect is 

 perfectly dry, becomes brown or yellow, with scarcely a tinge of 

 green in it. The exotic Cassidas, however, are often so splendid 

 and their colours so permanent, that several of the species, par- 

 ticularly those from South America, are often set in gold and 

 worn as jewels. 



The illustration on the next page gives a figure of a fine 

 Brazilian Tortoise Beetle, called Mesomphalia illustris. The 

 thorax is very flat and of a deep satiny green hue. It is 

 covered with punctures, and on either side there is a rather deep 

 depression. The elytra are curiously formed. They are rounded 



