XII 



INTRODUCTION. 



W"/"-' 



pass, onfe oi;) each side of the oesophagus, to the cephalic 

 ganglion, forming a nervous collar around the alimen- 

 tary canal. From each of the ganglia small nerves 

 branch to various parts of the body. Note the ceph- 

 alization of the nervous system in the adult insect. 



Reproductioti.— AW insects are dioecious. Instances 

 of agamic reproduction will be noticed later in the 

 course. 



METAMORPHOSES. 



Note carefully the meaning of the following terms.— 

 Larva, pupa, or chrysalis, imago, complete metamor- 

 phosis, and incomplete metamorphosis. 



CLASSIFICATION. 



-i^c 



Hexapoda, 

 k'S six, and novi foot. 



' Hymenoftera, 



v/ui/y, membrane, nrspov, wing. 

 Lei'idopteka, 



XtTcU, a scale, ntepov, wing. 

 Diptera, 



dU, two, nrtpovy wing. 

 COLEOPTERA, 



nnXioi, a sheath, ^rrfpoV, wing. 



Hemiptera, 



/////, half, TtTEpov, wing. 

 Oritioptera, 



op^oi, straight, mepov, wing. 



Neuroptera, 

 vevpov, a nerve, nTspov, wing. 



