CHAPTER XII. 



PEEDATOKY INSECTS. 



INSECTS PREYING UPON APHIS. 



LADY-BIRDS.— COCCINELLIDJE. 



Several species of this family have already beeu noticed as predatory 

 upon Scale-insects; nearly all the species, and they are very numerous, 

 l)rey to a greater or less extent upon Aphis. Of the larger forms, which 

 are familiar everywhere under the name of Lady-birds, four species are 

 commonly found feeding upon the Orange Aphis in our groves. They 

 are Ghilocorus bivulnerus (Muls.) ;* Exochomns contruiaius (Muls ) ;t Cy 

 cloneda sanguinea (Linn.);f and Hippodamia convcrgens Gu6r.§ These 

 have all been mentioned as preying upon scale-insects. Among the 

 smaller members of this family are numerous sjiecies of the genus Scym- 

 nus, which prey upon Plant-lice, and most of them are found from time 

 to time upon the orange trees. The form in Scymnns is rounded and 

 very convex; the color in most of the species is a somber brown, some- 

 times relieved with blotches of dull red or yellow. The body is always 

 hairy. In size the species range from one-tenth to one-twentieth of an 

 inch in length. They are apt to resemble each other closely, and in some 

 groups the species are distinguishable the one from the other only on 

 the closest analysis. 



The larva of Scymnus is rather thick and short, the body dark brown, 

 purple, or black, but entirely covered above with tufts of white wax, 

 which are easily rubbed off in handling the insect. 



The pupa is found within the split skin of the larva, as with the larger 

 species of Lady-birds. 



SCYMNUS CAUDALIS Lec. 



In this species the body is black, with the head and parts of the 

 thorax red ; the end of the body and the legs yellowish-red. Length, 

 2^^"" (tIf inch). 



160 



* Black, with two red spots. 



t Smaller in size. Ked, with two black spots. 



t Blood-rod or brick-red, without spots. 



$ Orange-redj mtk five or ei^ spotg on e^cl^ wi«g-ooy§F. 



