526 ME. A. D. MICHAEL ON THE 



Fig. 3. (Left middle of Plate.) The posterior part of the pharynx, tlic receptaculum cibi (suckiug- 

 stomach), and anterior jiart of the ojsophagus seen from the right side : x 70. The darkish 

 mass inside the receptaculum cibi is the food-contents. 



4. (Right top corner of Plate.) The receptaculum cibi, maxillary lip, and left palpus seen from 



above, x 70. The end of the lingua is shown protruded ; the oesophagus is hidden. 



5. (Right a little below centre of Plate). The anterioi' end of this figure points to the right. The 



pharyngeal plate and its levator (distcnsor pharyugis) muscles seen from the right side : 

 X 320. 



6. (Lower edge of Plate.) Ventriculus from above : x 30. This figure is drawn from a young 



female, mature, but only one egg showed any sign of yolk-segmentation. In older specimens 

 the form of the ventriculus is generally lost from distension and the pressure of other organs. 



7. (Lower edge of Plate.) The excretory (Malpighian) organ from the left side: X 120. The 



white matter within the viscus is the secretory (urinary ?) matter. 



8. (Left top corner of Plate.) The tubular, leniforni, and anterior salivary glands on the left side 



of the body with their common duct : X 120. The reniform gland is seen almost on edge. 

 This drawing is slightly diagrammatic in the sense that it is not quite drawn] to scale (to 

 avoid waste of space) and that the parts are a little separated in order to show them. 



9. (Lower left corner of Plate.) The left reniform salivary gland and duct seen from the side : 



X 120. The duet is cut short. 



10. (Right centre of Plate.) The azygous and pericibal salivary glands with their ducts in situ in 



the body, seen from above : x 55. A small part of the posterior end of the receptaculum 

 cibi is seen between the pericibal glands. 



11. (Right lower corner of Plate.) The azygous and the left pericibal salivary glands with their 



ducts seen from the inner side : x 120. The azygous is to the left, the pericibal to the 

 right of the figure; the duct from the latter is cut short. 



12. (Below centre of Plate.) Sagittal median section through the azygous salivary gland oi Bdella 



vulgaris : x 1 80. 



13. (Central upper figure.) The brain and nerves seeu from above : X 100. The hole where the 



oesophagus passed between the supra-cesophageal and the sub-cesophageal ganglia is shown, 

 but the oesophagus itself has been removed, except a small portion anterior to the brain. 

 The nerve to the receptaculum cibi has been tui'ued a little to the right to show the 

 pharyngeal nerve from which it springs and which it would hide. The mandibular nerve is 

 turned a little outward, as it would lie over the palpal nerve. The left genital nerve is 

 slightly turned over to show the branches on its under surface. The whole length of the 

 optic nerve is shown ; the other nerves are cut short. 



14. The branching of the mandibular nerve : x 200. 



15. The termination of the labial branch of the palpal nerve in the maxillary lip : x 400. 



16. One of the dermal glands and duet : x 700. 



Plate 42- 



Fig. 17. The reproductive organs of the male spread out so as to show details : x 70. The embedding-sacs 

 {es) are turned to the right and lelt, carrying their respective pairs of testes with them; in 

 situ they would lie close together, present their edges to the observer, and hide the testes 

 between them ; the azygous accessory gland would be more closely jiressed by the great 

 mucous glands, which would probably hide the laminated gland. The almost globular organ 

 in the centre of the group is the head of the peuial canal looked down on perpendicularly ; 

 the glandular antechambers are seeu entering it. The laminated gland is seen in the median 



