84 ILUNOIS BIOLOGICAL MONOGRAPHS 1204 



EXPLANATION OF PLATE 



Gordius robustus 



Fig. 39. — Cross section in front of cephalic ganglion in specimen shedding the larval cuticula; 



X90. 

 Fig. 40. — ^Longitudinal section of specimen with adult cuticula nearly completed; shows spine 



in early development with minute fibre barely traceable to hypoderm; X 870. 

 Fig. 41. — Hypoderm and the formation of granular layer under larval cuticula; X 500. 

 Fig. 42. — Cross section of specimen with developing cuticula; shows nerve cell and fibre in 



hypoderm; X 450. 

 Fig. 43. — Stage in the development of adult cuticula later than that shown in Fig. 35; cuticula 



has attained about half its final diameter; X 450. 

 Fig. 44. — ^Late stage in development of adult cutiaila, longitudinal section; shows bristle 



passing thru granular layer; X 665. 

 Fig. 45. — Section parallel to neural lamella in specimen nearly mature; shows bipolar cells; 



X 320. 

 Fig. 46. — Cross section thru body of female that has deposited its eggs; shows tissues partly 



degenerated; X 135. 



