THE NATURAL ENEMIES OF THE CITRUS MEALY 



BUG II. 



BY E. O. ESSIG 



HORTICULTURAL COMMISSIONEK OF 



VENTURA COUNTY, CALIFORNIA 



Coccinellidse 



Among the ladybird beetles come many of the predaceous enemies of 

 the mealy bug, and because of their great importance to the entire field of 

 Agriculture and Horticulture in combating especially the Coccid and Aphid 

 pests, we have been studying as many of its species as possible. To my 

 knowledge there are no works in the state dealing with the accurate dis- 

 tinguishing of the larval and pupa forms and to this end this study is being 

 attempted. To the practical observer the larvx and pupse are rarely as- 

 sociated with the correct adult. Since it is the larva that we expect to do 

 most of the good work, we should be able to distinguish it immediately. At 

 present we have at Santa Paula the following ladybird beetles as enemies of 

 the mealy bug; Cryptolaoiins inontrouzieri, Rhizobins vciifralis, Rbizobius 

 lophantlia. Scyviuus giittulatiis, and several others not determined. These 

 we shall consider first. In order to better understand the descriptions let 

 us look first at the general characters of the larvae. 



Family Characters of Larvae of Coccinellidfe* 



Larva six-footed, with ventral side of the body straight — an adaptation 

 for crawling on a plane surface. Abdomen with nine segments, the last con- 

 taining an anal tube which is used in locomotion. 



Spiracles are located as follows : One pair on the mesothorax and a pair 

 on each of the first eight abdominal segments. These spiracles are situated 

 on the lateral margins near the middle of the segments, and extend to a 

 considerable distance within the body. 



Head small, hard, narrower than pro-thorax. Epistoma large at the 

 fore part widening from a narow front towards the crown of the head 

 where it becomes almost circular. Clypeus distinctly separated from the 

 frontal by a well defined suture. 



Ocelli protruding, situated on a triangle just behind the antennae. 



AntennK situated on the lateral anterior angles of the head just back 

 of the base of the mandil)les : three-articled, very small and retractible. The 

 of the base of the mandibles; three-articled, very small and retractile. The 

 inserted on the exterior margin of the second. Tt is shorter, more slender 

 than the second and usually terminates in a point. 



Mouth-parts small and not extended. Labruni membranous, irregidar 

 on the front, extending between the lateral angles of the clypeus. which 

 is much more chitinous. Mandibles strong, somewhat triangular, nearly 

 as wide at the base as long, .sharp-pointed, hut generally bifurcate at the 

 point, with a tooth on either side or with one on botli sides near the base. 



•Geo. W. Dimmock — Algunas CocclnelUdae de Cuba, 1905. 



