IN NEW MEXICO. 



a small dot of a darker color than the rest of the scale. This marks 

 the location of the cast skin or skins (exuviae) lying beneath the 

 scale, and its position serves as a character for distinguishing differ- 

 ent species and even genera of this sub-family. 



Lecaninae. Examples are the various species of Lecanium, to 

 which belong the black scale of California; the cottony maple- 

 scale (Pnlvinaria innumerabilis Rathv. ) ; and the lac insect (Carter ia 

 lacca Ker. ). In the genus Lecanium the female lays her eggs be- 

 neath the scale, and secretes no cottony material. In the genus 

 Pulvinaria the female secretes a mass of cottony material, in which 

 the eggs are deposited. 



Monophloebinae. Examples are the various species of Icerya, to 

 which belongs the famous fluted scale, so destructive to the orange 

 in California and originally brought from Australia ; also the mes- 

 quite scale mentioned in this bulletin, and which will probably form 

 a new genus. There are some gigantic species of this sub-family in 

 Australia, some of them reaching, the length of nearly two inches ! 



Coccinae. Examples are the cochineal insect (Coccus cadi L.); 

 and the mealy bugs (Daotylopiu8\. 



GENERAL HABITS OF SCALE-INSECTS. 



The female scale-insect is always wingless, and does not undergo 

 a complete metamorphosis. She fixes her beak in the bark, stem, 

 leaf, or fruit while young, and becomes stationary (except the Mon- 

 ophlochlnac and Coccinae), excreting and forming her scale as she 

 grows. 



The male, however, of all scale-insects undergoes a complete 

 metamorphosis, and is furnished in the adult state with a single pair 

 of wings. The hind pair is wanting, but is represented by a pair of 

 club-like appendages called halteres or balancers. Each of these 

 appendages is furnished with a hooked bristle, which fits into a 

 pocket on the margin of the wing of the same side, and doubtless 

 serves to brace and strengthen the flight. The adult male has no 

 organs for obtaining food, and takes no nourishment, his sole 



