108 ILLINOIS BIOLOGICAL MONOGRAPHS [228 



EXPLANATION OF PLATE 



Fig. 127. — Gordius robustus, tangential section of hj^joderm of young specimen; shows nuclei 

 and nucleoli as well as radiating canals; X 800. 



Fig. 128. — G. robustus, tangential section thru hypoderm of specimen in which fibrous cuticula 

 is forming; intercellular bridges; X 400. 



Fig. 129. — G. robustus, section similar to that of Fig. 128; nerve fibre in hypoderm; X 475. 



Fig. 130. — Paragordius varius, young parasite in the coiled stage; X 190. 



Fig. 131. — P. varius, very young parasite; side view; specimen somewhat flattened; X 250. 



Fig. 132. — P. varius, anterior end of adult; side \aew; semi-transparent; X 70. 



Fig. 133. — P. varius, posterior end of adult male; ventral view, shows rows of bristles; X 70. 



Fig. 134. — P. varius, cross section of host containing young parasite; X 37. 



Fig. 135. — P. varius, section of parasite from Fig. 134; X 130. 



Fig. 136. — P. varius, cross section thru middle of body of 3'oimg specimen; early development 

 of gonads; X 500. 



Fig. 137. — P. varius, spermatozoa; smear made from male; X 800. 



Fig. 138. — P. varius, spermatozoa; smear made from seminal receptacle of female; X 800. 



Fig. 139. — P. varius, longitudinal section parallel to large nerve cells in ventral cord; shows 

 bipolar cells; X 250. 



