Explanation of Plates. 91 



Fig. 85. Ovum showing characteristic ribbed appearance of collapsed ova; 



length 0.075 mm. 

 Fig. 86. Ventral view of head of specimen from H. plumieri. Diameter of 



head 0.15 mm. 



Lechradena edcntula gen. et sp. nov., from Neomcenis griseus. 



Fig. 87. Ventral view, life, details added; length 2.10 mm. 



Plate ii. 

 Mesorchis urna gen. et sp. nov. 



Ventral view, life, details added, uterus diagrammatic; length 2.5 

 mm. From Pomacanthus arcuatus. 



Dorsal view, balsam, excretory vessel diagrammatic and added from 

 another specimen; length 1.5 mm. I, opening of Laurer's canal. 



Tangential section showing excretory pore, Laurer's canal (I), cirrus, 

 seminal vesicle, ovary, shell-gland, etc.; thickness of body at this 

 point 0.26 mm. Sketch made from 3 adjacent sections. 



From horizontal section, showing ventral sucker, metraterm, and 

 cirrus-pouch; diameter of ventral sucker 0.14 mm. 



Transverse section, showing ventral sucker, metraterm, branches of 

 excretory vessels, posterior end of one testis, uterus, and yolk- 

 duct; breadth 0.4 mm. 

 Fig. 93. Transverse section near posterior end, showing single excretory 

 vessel, h, wall of branch of excretory vessel which is cut through 

 in next section anterior to this; breadth 0.4 mm. 



Diplangus paxillus gen. et sp. nov., from Hcemulon macrostonium . 



Fig. 94. Lateral view, life, details added; length 1.35 mm. 

 Fig. 95. Dorsal view, life, details added; length 1.47 mm. 

 Fig. 95a. Ovum; length 0.041 mm. 



Plate i 2 . 

 Diplangus paxillus, continued. 



Fig. 96. Lateral view, life, details added, somewhat diagrammatic; length 

 1.38 mm. From H. plumieri. The prostatic portion of the cirrus- 

 pouch also contains a part of the seminal vesicle. 



Fig. 96a. Ova; length 0.041 mm. 



Fig. 966. Outline, showing a common form, lateral view; length 1 mm. 



Fig. 97. Ventral view, life, details added; length 1.75 mm. 



Fig. 98. Transverse section through pharynx and cirrus-pouch. From H. 

 sciurus. 



Fig. 99. Nearly transverse section through neck, showing subcuticular 

 glands which seem to be yolk-forming glands. Thickness of 

 body at this point 0.08 mm. From H. plumieri. 



Fig. 100. Nearly transverse section through seminal vesicle, a few cells of 

 subcuticular glands showing. Thickness of body here 0.01 mm. 

 sv', prostatic part of seminal vesicle. 



Fig. i 01. Nearly transverse section through prostate gland and seminal 

 vesicle and ventral sucker. From H. sciurus. 



Deretrema fusillus gen. et sp. nov. 



Fig. 102. Ventral view, life, details added ; length 2.10 mm. Uterus some- 

 what diagrammatic. Contents of esophagus deeply stained. 

 From Ocyurus chrysurus. 



Fig. 102a. Ova, life; length 0.034 mm. Left ramus of intestine appeared to 

 pass ventrad of cirrus-pouch as indicated in sketch. 



Plate 13. 

 Deretrema fusillus, continued, from Hcemulon macrostonium. 



Fig. 103. Ventral view, life, details added; length 1.68 mm. 

 Fig. 104. Dorsal view, balsam; length 1 mm. 

 Fig. 104a. Ova, one collapsed; length 0.04 mm. 



