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Pomona College Journal of Entomology 



end and transforms within the cottony case of the larval stage. The form 

 gradually assumes a round shape and in this way the pupae may be told 

 from the larvae. 



Nymphs or Pupae. (Fig. 134 B). The drawing shows the pupal or 

 nymphal bodv after it has been removed from the larval case in which it 

 transforms. As is seen it shows the characteristic spines on the body as is 

 shown in the three other members of the Scymnini, all of which are covered 

 with the white cottony wax. The normal covered form of the nymph is 

 about that of pupa, except that it gradually shortens up into somewhat of 

 a spherical form. The body proper averages 2 mm. in length and 1 mm. in 

 width. It requires from three weeks to a month for the insects to pass 

 through this stage, but during the winter they may remain in the pupa cases 

 for several months, if the weather is cold and damp. 



It is noticeable that the spines on the lateral margins of the abdomen do 

 not appear on the three last segments, while in Scymnus guttulatus they 

 extend to the last segment and in Cryptolacmus montrouzieri the same is 

 also true, except that the spines are few on the next-to-the-last segment also. 



Adult (Fig. 134 C). The adult insect appears, at first sight, to be black, 

 but upon closer examination it will be found that the background is black with 

 one quite large reddish-brown spot on each elytra as shown in the drawing. 

 The form is elongate oval. Length, 2.5 mm., width, 1.1 mm. The entire 

 body is finely hirsute. Eyes hairy. Punctures on elytra finely set. Pro- 

 thorax narrower than rest of body proper. Antennae small, hairy. Maxillary 

 palpi, large. Labial palpi, normal. Mesothorax and metathorax nearly equa' 

 in length, the latter slightly broader. Coxae not approximate. Trochanters 

 small. Femora large but short, tibia nearly as long as femurs, but much 

 narrower. Tarsi two-thirds as long as tibia. Claw normal. First abdominal 

 segment as long as the second and third. 



The adults are most active and difficult to capture in the field. They take 

 to wing as soon as disturbed or crawl in some small crevice with such 



Figure 135. The Ladybird Beetles predaceous on the Citrus Mealy Bug: 

 A, Cryptolaenuis montrouzieri; B, Kliizobiiis ventralis; C, Cryiitogoiiius orbiculus; 

 D, Scymnus guttulatus. 



