4i0 



Observations on the various Insects 



which greatly alters the aspect of this visitation ; for it seems the 

 farmer need not despair of a crop recovering from the depreda- 

 tions of these larvae. Mr. Maxwell says, " The beet- root plants 

 which remained after ploughing up the field, and whose leaves 

 suffered in the manner represented to you, have altogether reco- 

 vered from their injuries, and are in a most flourishing state; so 

 much so, that from my experience of this year I should certainly 

 not recommend the course adopted last year, but trust to the plants 

 recovering the injuries sustained by them during the month of 

 June, before the larva has buried itself to undergo its transforma- 

 tions, I observed again that the larvae totally disappeared about 

 the 1st of July, appearing first on the 4th of June. Most un- 

 doubtedly the leaves are the only part of the plant fed on by the 

 insect, the roots being perfectly untouched." 



Cassida nebulosa. The Clouded Shield-Beetle. 



M. Bazin, a proprietor at Mesnil St.-Firmin, to the south of 

 Paris, detected in 1846 considerable numbers of the curious larvae 

 of this beetle feeding upon the leaves of the red-beet. They re- 

 side on the under side of the leaves, which they nibble by degrees 

 in small round spaces, and the leaves are thus riddled with little 

 holes.* They also inhabit Chenopodium liyhridum (the Maple- 

 leaved Goosefoot), and feed upon the leaves in July. 



The larvae are of a pretty green colour, marked with white, and 

 the margins of the body are armed with barbed yellow spines 

 (fig. 25) ; they are oval and depressed, with a small scaly head, 

 furnished with teeth and three minute eyes in an oblique line, 

 like little black tubercles, and four others higher up ; each side 

 is furnished with sixteen sharp spines, which are very^bristly ; at the 

 extremity of the body are two long spreading tails, which the animal 

 turns over the back when at rest, to support its shrivelled cast-off" 

 skins and excrement, which, like a parasol, shade it from the sun, 

 and also protect it from being stung by parasites, but these tails 

 are stretched out when the larva walks : the six pointed legs are 

 concealed beneath the thorax. When they are prepared to change 

 to pupae, they fix themselves by the under side of the belly to the 

 leaf which nourished them, and partially throw off" their skin in 

 two or three days. The appearance of this pupa is more remark- 

 able than that of the larva; it is oval and depressed, with a large 

 shield-like thorax entirely concealing the head ; the margin is 

 ciliated, and there are two white spots on the back ; the segments 

 of the body are cut on the sides like the teeth of a saw, the ter- 

 minal one is spiny, and produces a forked tail : it is of a bright 

 and lively green colour, with the margins of the thorax and abdo- 



* Annales de la Soc;. Ent. de France, for 1846, p. Ixxi. 



