THE LILY AND POPLAR BEETLES. 141 



surface blue-blacky the thorax red, spotted with black, 

 and the elytra yellowish, adorned with a black cross, 

 and some black spots. This pretty little beetle when 

 held in the fingers is able to produce a slight creaking 

 noise by the friction of the extremity of the abdomen 

 against the margin of the elytra. The larva is a 

 short, fleshy, dingy grub, thickest towards the pos- 

 terior extremity, and furnished with six short legs, 

 and with a double series of fleshy tubercles along the 

 lower surface of the abdominal segments, which also 

 serve as legs. The larv?e of some allied species have 

 the anal opening placed on the upper surface of the 

 last segment of the body, and the excrementitious 

 matter is by this means gradually pushed up along 

 the back of the larva, affording it a screen similar to 

 that possessed by the curious larva of Cassida. One 

 species, which is often found on the white lily in 

 gardens, has received the name of Crioceris merdigera 

 from this circumstance. 



Of the typical, ovate, and very convex species of 

 this tribe, one of the commonest is the Melasoma 

 Populi, an insect nearly half an inch in length, of a 

 shining blue-black coloiu", with the elytra red, and a 

 small black spot at the extreme tip of each. It is 

 found on poplars and willows, of which it devours the 

 leaves; and when it abounds on low sallows, those 

 shrubs often exhibit a most melancholy appearance. 

 The larva, which has the same habits as the imago, 

 is thick and fleshy, furnished with six legs, and 

 with rows of tubercles along its back and sides; 

 its colour is a dirty greenish white, with nume- 

 rous black spots. It undergoes its transformation 

 attached to the leaves, from which the pupa is sus- 

 pended by the tail like the chrysalis of a butterfly. 



