260 HUGH WATSON. 



PLATE IX. 



Fig. 27. — X 2A. Apera gibbonsi rubella; general dissection 

 from above.' 



Fig. 28. — x 5. A. parva; general dissection from above. 

 Fig. 29. — x 45. A.dimidia; general dissection fi-om above. 

 Fig. 30. — x 2. A.burnupi; general dissection from above. 

 Fig. 31. — x 2f. A. sexangula; general dissection from above. 



PLATE X. 



Fig. 32. — x 25. Apera gibbonsi rubella, young; transverse 

 section through the region of the buccal retractors. - 



Fig. 33. — x 25. A. gibbonsi rubella, young; transverse section 

 through the region of the anus. 



PLATE XI. 



Fig. 34. — x 25. Apera dimidia; transverse section through the 

 region of the heart. 



Fig. 35. — x 25. A.dimidia: transverse section through the region 

 of the reno-pericardial duct. 



PLATE XII. 



Fig. 36. — x 25. Apera dimidia; transverse section through the 

 region of the anterior end of the ureter. 



Fig. 37. — X 128. A. dimidia; transverse section through the 

 skin of the back. 



Fig. 38. — x 300. A. dimidia; transverse section through the 

 skin of the foot-sole. 



Fig. 39. — X 118. A.dimidia; transverse section through the right 

 corner of the lung. 



PLATE XIII. 



Fig. 40. — x 300. Apera dimidia; transverse section through a 

 sphincter of a dennal blood-vessel. 



' The specimens shown in figs. 27-31 have been cut open a little to 

 the left of the mid-dorsal line, and, excepting in A. burnupi, the 

 digestive and i^eproductive organs have been slightly separated in order 

 to show the course of the anterior aorta. 



- The sections rej)resented on Plates X to XII are shown as viewed 

 from the front. 



