Plate IV. 



Fig. 24. Male. Caudal end. Apochr. 8 mm. Comp. 4. 



— 25. Larva from the Prothorax of Periplaneta americana Apochr. 2 mm. Comp. 4. After a 



living specimen. 



— 26. Larva from the Prothorax of Periplaneta americana. Front end. Apochr. 2 mm. Comp. 4. 



— 27. Male. Testes. Ves. sem. Apochr. 8 mm. Comp. 4. 



— 28. Larva from the ventricle of a rat, four days after the feeding with 60 cockroaches. 



Apochr. 8 mm. Comp. 4. After a living specimen. 



— 29. Male. The bent cephalic end of the Testis. Apochr. 8 mm. Comp. 8. 



— 30. The tip of the long spicule. Apochr. 2 mm. Comp. 4. 



— 31. The short spicule, a part of the long spicule and the chitinous sheath-apparatus. Apochr. 



2 mm. Comp. 4. 



— 32. Larva from the Prothorax of Periplaneta americana. Apochr. 8 mm. Comp. 4. After a 



living specimen. 



XXV. 



