ART. 7 CESTODE PARASITES OF BIRDS LINTON 69 



82. Transverse section of proglottis : genitalia supplied from about five 



sections ; diameters 1.26 by 0.77 mm. 

 S3. Transverse section of ripe proglottis ; diameters 1.05 by 0.28 mm. 



84. Frontal section of ripe proglottis ; breadth 1.09 mm. 



85, 86, 87. Transverse sections of cirrus and cirrus-poucb. from sagittal 



sections of proglottis ; diameters of cirrus, 0.056, 0.07, and 0.09 mm. 



88. Longitudinal section of cirrus and cirrus-pouch, from frontal section 



of proglottis ; diameter of cirrus-pouch 0.11 mm. 



Hymenolepis coronula (Dujardin) 



89. Scolex ; diameter of sucker 0.06 mm. ; from Oidcmia perspicillata. 



90. Front vievp of scolex ; diameter of sucker 0.07 mm. 



91. Transverse section of proglottis ; longer diameter 1.61 mm. 



92. Adult proglottis ; length 0.50 mm. ; from Glaucionetta clangula ameri- 



cana. 



Plate 8 



Hymenolepis coronula (continued) 



Fig. 93. Transverse section of genital cloaca ; camera lucida drawing, Spencer 

 6/4 mm. 



Hymenolepis ductilis, new species, from Larus argentatiis 



94. Scolex and portion of strobile ; diameter of scolex 0.26 mm. 



95. Tip of rostellum ; length of hooks 0.039 mm. 



96. Ventral view of young proglottis ; breadth 0.33 mm. 



97. Ventral view of proglottides ; breadth 0.35 mm. 



98. Dorsal view of young proglottis ; breadth 0.30 mm. 



99. Lateral margin of proglottides ; length of proglottis 0.05 mm. 



100. Ripe proglottides ; breadth 0.35 mm. 



101. Transverse section of rii«i proglottis ; diameters 0.39 by 0.15 mm. 



Hymenolepis fusus (Ki-abb) from Larus argentatus 



102. Scolex ; diameter 0.10 mm. 



103. Hooks from rostellum ; length 0.02 mm. 



104. Posterior end of strobile ; maximum breadth 0.28 mm. 



Hymenolepis macracanthos (Linstow) from Mcrgus senator 



105. Scolex ; diameter 0.13 mm. 



106. Hook from rostellum ; length 0.09 mm. 



107. Dorsal view of young proglottis; rudiment of ovary showing through 



from ventral side ; breadth 0.50 mm. 



108. Dorsal view of older proglottis, testes not seen ; breadth 0.47 mm. 



109. Ripe proglottis, with remnant of ovary ; breadth 0.48 mm. 



110. Ripe proglottis ; breadth 0.53 mm. 



111. Cirrus; diameter of bulbous base 0.036 mm. 



112. Section of base of cirrus ; diameter 0.030 mm. 



