92 Papers from the Marine Biological Laboratory at Tortugas. 



Distomum fenestratum Linton, from Hamilton plumieri. 



Fig. 105. Ventral view, life; length 3.5 mm. 



Fig. 106. Transverse section near posterior end, somewhat diagrammatic; 

 breadth 0.25 mm. 



Xystretrum papillosum gen. et sp. nov., from Lactophrys triqueter. 



Fig. 107. Ventral view, balsam; length 3.5 mm. Folds of the uterus dia- 

 grammatic. The ova are really much more numerous than 

 represented, c, cirrus extruded; n, ventral corrugated disk. 



Fig. 107a. Spines from posterior border enlarged. 



Fig. 108. Papillary spines lining mouth cavity; diameter of mouth 0.16 mm. 



Fig. 109. Papillary spines on ventral sucker; diameter of ventral sucker 

 0.21 mm. 



Fig. 1 10. Transverse ridges of ventral disk. 



Fig. hi. Outline of vitelline glands. 



Hysterolecitha rosea gen. et sp. nov., from Teuthis hepatus. 



Fig. 112. Ventro-lateral view, life, details added; length 3.36 mm. 

 Fig. 113. Ovary and vitelline glands seen from right side; longer diameter 

 of ovary 0.11 mm. 



Plate 14. 



Hysterolecitha rosea, continued, from Teuthis hepatus. 



Fig. 114. Ejaculatory duct, seminal vesicle, and metraterm, life; highly 



magnified, pr, cell's surrounding genital aperture. 

 Figs. 115, 116, 117. Sketches of ovary, vitelline gland, and seminal receptacle 



from different specimens. 



Macradena perfecta gen. et sp. nov., from Teuthis cceruleus. 



Fig. 118. Sketch made up from about 3 adjacent, horizontal sections, some- 

 what diagrammatic; length 2.55 mm. 



Fig. 119. Part of transverse section through seminal receptacle, yolk-gland 

 and shell-gland; diameter 0.45 mm. 



Opisthadena dimidia gen. et sp. nov., from Kyphosus sectatrix. 



Fig. 120. Ventral view, life, details added; length 2.80 mm. 

 Fig. 120a. Ova; length 0.038 mm. 



Fig. 121. Dorsal view, made up from horizontal sections, diagrammatic; 

 length 5 mm. 



Plate 15. 



Opisthadena dimidia, continued. 



Fig. 122. Transverse section showing extraordinary development of longi- 

 tudinal muscles of body-wall and of walls of intestine; diameter 

 0.45 mm. 



Brachadena pyriformis gen. et sp. nov. 



Fig. 123. Ventral view, life, details added; length 1.61 mm. From H&mulon 



plumieri. 

 Fig. 123a. Ovum; length 0.037 mm. 

 Fig. 124. Ventral view of small specimen, balsam; length 0.65 mm. From 



H. sciurus. 

 Fig. 125. Sagittal section of neck; diameter of oral sucker 0.010 mm. From 



Calamus calamus. 

 Fig. 126. Ventral view of cirrus-pouch, balsam. From H. plumieri. 



Dichadena acuta gen. et sp. nov. 



Fig. 127. Ventro-lateral view, balsam; length 1.55 mm. From Teuthis 

 cceruleus. 



