340 ILLINOIS BIOLOGICAL MONOGRAPHS [340 



EXPLANATION OF PLATE 



Fig. 116. — Proteocephalus ambloplitis (Leidy), head, frontal section showing 

 vestigial fifth sucker. After Benedict. 



Fig. 117. — Proteocephalus ambloplitis (Leidy), head, toto. After Benedict. 



Fig. 118. — Proteocephalus exiguus La Rue, ripe proglottid showing arrange- 

 ment of organs. After Benedict. 



Fig. 119. — Ophiotaenia lonnbergii (Fuhrmann), head, toto. After Fuhrmann. 



Fig. 120. — Proteocephalus percae (Midler), head, frontal section showing fifth 

 sucker. After Schneider. 



Fig. 121.— Proteocephalus percae (Miiller), head, toto. Reproduction of M til- 

 ler's figure 2. 



Fig. 122. — Proteocephalus percae (Miiller), head, toto. Reproduction of Mid- 

 ler's figure 3. 



Fig. 123. — Crepidobothrium gerrardii (Baird), head, toto. After Monticelli. 



Fig. 124. — Crepidobothrium gerrardii (Baird), head, toto. After Monticelli. 



Fig. 125. — Monticellia macrocotylea (Monticelli), head. After Monticelli. 



Fig. 126. — Proteocephalus pentastoma (Klaptocz), anterior face of head. After 

 Klaptocz. 



Fig. 127. — Proteocephalus pentastoma {Klaptocz), head and neck. After Klap- 

 tocz. 



Fig. 128. — Proteocephalus pentastoma (Klaptocz), portion of middle of worm. 

 After Klaptocz. 



Fig. 129. — Proteocephalus pentastoma (Klaptocz), posterior part of worm. 

 After Klaptocz. 



Fig. 130. — Proteocephalus sulcatus (Klaptocz), head, anterior face. After 

 Klaptocz. 



Fig. 131 — Proteocephalus sulcatus (Klaptocz), head. After Kloptocz. 



Fig. 132. — Monticellia coryphicephala (Monticelli), head, toto. Note the prom- 

 inence of the suckers. After Monticelli. 



