356  Nature  and  Structure  of  Cochineal.    {Am;uJg°u";  gg111, 
of  the  abdomen  (Fig.  2).  One  or  both  of  the  antennae  are  fre- 
quently present,  showing  5  to  7  parts.  The  joints  of  the  legs  are 
usually  more  or  less  detached,  the  point  of  insertion  usually  only 
being  indicated  by  large  yellowish-brown  elliptical  areas.    In  be- 
Fig.  5. 
Microphotograph  of  larva  in  cochineal  insect  of  commerce  showing:  outspreading  antennas  (a) 
and  feet  (/);  the  characteristic  beak  or  proboscis  (&);  and  wax-hairs  on  the  body  (h). 
tween  each  of  the  legs  on  both  sides  are  situated  2  distinct  pores, 
resembling  in  form  and  color  the  point  of  attachment  of  the  legs, 
and  which  are  tracheae  or  respiration  canals.  Covering  the  body 
we  find  on  surface  view  numerous  small  groups  of  cells  with  thick 
yellowish-brown  walls.  When  seen  in  section  they  are  more  or 
less  conical  and  traversed  by  open  canals.   These  have  been  studied 
