106 CALIFORNIA STATE COMMISSION OF HORTICULTURE. 



scales. Coccinella oculata is a still larger form often taken for the 

 "twice-stabbed" ladybird. Exochormis pihttei, " Pilate's ladybird," also 

 resembles the "twice-stabbed," but the under side of the abdomen is. 

 black instead of red. It feeds on black scale, but does not increase 

 rapidly. Psyllohora 20-mnculala, the " 20-spotted ladybird," is a com- 

 mon species, feeding on young scale and the red spider. 



Of the ladybirds introduced by the State Commission of Horticulture, 

 Vedalia cardinalis, Rhizobius ventralis, R. twoomhese, Novius koebelei, 



Orcus chalyheus, Cryptolse- 

 I , mns montrouzieri, Scymnus 



V-^*-V vagaois, S.marginicola, Rhizo- 



.y'^^Z^^^^^ bins debilis, Rhizobius lopan- 

 ''^fcZ^cv^ i/ia, and Hyperaspis lateralis 

 'j ^~ "^ "^ci"^ have proved the most suc- 

 "">^gr~y^C; cessful. Vedalia cardinalis 

 ' ^^-?f f? ^^^ Noviiis koebelei have com- 

 -■;i^^r'^' pletely subjugated the cot- 

 FiG.ioo. Novius koebelei. touy-cushion scalc. Ovcus 



chalybeus is effective against 

 the yellow scale. Rhizobius ventralis is a very useful destroyer of the 

 black scale. Scymnus vagans is an enemy of the red spider. Rhizobius 

 lopnntha, makes some headway against the purple scale, and Cryptolxmus 

 montrouzieri cleans up the mealy-bugs in greenhouses. The other 

 species are general feeders. 



If it were not for these industrious enemies of our fruit and vine 

 pests, California would be far from ranking to-day the chief fruit- 

 producing State of the Union. 



Section HETEROMERA. 



This section is a rather miscellaneous lot of beetles, including several 

 small obscure families, as well as two large ones. All those beetles 

 which have the front and middle feet with five tarsal segments and 

 the hind feet with four are included in it. 



The family Tenebpionidse are the "darkling beetles." They are usu- 

 ally dark brown or black in color, oblong or oval in shape, have the 

 head more or less inserted in the prothorax, and, on account of their 

 long legs, are very awkward in their movements. Both adults and 

 larvae are scavengers, the latter much resembling wireworms in appear- 

 ance. The common pinch-bug, Eleodes sp., which when disturbed 

 stands on its head and emits an ill-smelling fluid, is a familiar type. 

 The meal-worm beetle {Tenebrio molitor), bred by bird fanciers for 

 food, and Tenebrio obscurus, found about stored grain products, are 

 cosmopolitan species. 



