STRUCTURE OF COCKROACH 



371 



They are omnivorous in their diet, active in their habits, 

 hiding during the day and feeding at night. They are 



mp 



Fig. 210. — Mouth -parts of cockroach. — From a Specimen. 



MN., Mandibles with iutenial cutting teeth. 



CA., Cardo of first maxilla, and ST., the stipes, the two forming the basal piece 

 or protopodite. 

 L., Lacinia, and G., the galea, the two forming the inner piece or endopodite. 

 MX. P., The five-jointed maxillary palp, the exopodite. 



SM., The sub-mentum of the second maxilla or labium, and M., the mentum, the 



two forming the basal piece or protopodite. 

 LA., Lacinia, and PG., the paraglossa, the two forming the inner piece or endo- 

 podite (sometimes called the ligula). 

 L.P., The three-jointed labial palp, the exopodite, rising from a little process or 

 palpiger of the mentum. 



ancient insects, for related forms occurred in Silurian ages ; 

 they are average types, neither very simple nor very highly 



