PLATE 5 



EXPLANATION OF FIGURES 



33 to 37 Drawn from frontal sections of the heads of nymphs of L. flavipes. 

 Oc. 10, obj. 16, table level. 



33 Anterior part of the brain of a newly hatched nymph, reproductive type; 

 showdng the hypodermal invagination of the frontal gland. 



34 Middle part of the brain of a newly hatched nymph, reproductive tj'pe; 

 showing the empty basement membrane of the frontal gland. 



35 Anterior part of the brain of a newly hatched nymph, worker-soldier 

 type; showing the first stage of the frontal gland, with no hypodermal invagina- 

 tion, but W'ith the fontanel muscles. 



146 



