C. M. Wen YON 
343 
PLATE XV. 
Lankesteria culicis (Ross 1898) a gregarine of Stegomyia fasciata- 
Fig. 1. Two gregarines encysted in the malpighian tubes of the pupa. 
Fig. 2. Nucleus of one of the gregarines of fig. 1, showing a process budding from the 
karyosome. 
Fig. 3. Another gregarine cyst in the malpighian tubes of a pupa. The deeply staining 
body between the gregarines is the remains of the fixation organs wliich are applied 
to one another when association takes place. 
Fig. 4. Section through a gregarine cyst. The nucleus of one of the gregarines shown is 
breaking up. In the next section in the series (fig. 6) is seen the beginnings of the 
first nuclear spindle. 
Fig. 5. A gregarine in the gut epithelium of a larva. Length of gregarine 45 jx. 
Fig. 6. See fig. 4. 
Fig. 7. A later section from the same cyst as fig 1. The dark body arising from the 
fixation organs is shown well. 
Fig. 8. A gregarine in the epithelium of the gut of a larva. Drawn on a larger scale than 
fig. 5. Length of gregarine 50 g. 
Fig. 9. Longitudinal section through a malpighian tube of a pupa showing many gregarine 
cysts. Note the excavations of the tube cells. 
Fig. 10. Gregarine cyst in malpighian tube of pupa showing zygotes and residual proto¬ 
plasm containing unused nuclei. 
Figs. 11, 13, 15 and 16. Stages in the conjugation of the gametes and nuclear fusion. 
The unequal size of the nuclei of the conjugating gametes is shown well in figs. 11, 
13 and 15. 
Figs. 12 and 14. Gametes showing the clear hyaline pointed structure near the nucleus. 
Fig. 17. Gregarine cyst from a malpighian tube of a pupa showing gametes. 
Fig. 18. Formation of gametes by a process of budding. 
Fig. 19. Gregarine cyst from a malpighian tube of a pupa. Last stage in nuclear 
multiplication. In one gregarine, very much ramified, the nuclei are ranged on the 
surface for gamete formation. In the other gregarine can be seen nuclear division 
spindles presumably of the last division. Many large unused nuclei are seen. 
Fig. 20. Gregarine cyst from a malpighian tube of a pupa. The zygotes have become 
elongated preparatory to formation of sporocysts. 
Figs. 21-27. Stages in the development of the sporocysts. 
Figs. 28 and 29. Nuclear spindles of the third nuclear division of a gregarine. 
Fig. 30. Karyosome free in protoplasm of the same gregarine from which tigs. 28 and 29 
were drawn. 
Figs. 31 and 32. Two adjacent sections through a gregarine cyst from a pupa. Fig. 31 
shows the breaking up karyosome and the complete disappearance of the nuclear 
membrane of the gregarine nucleus. Fig. 32 a structure which is probably the 
forming first nuclear spindle. 
Figs. 33 and 34. Dividing nuclei (third division) from the gregarine which was associated 
with the one from which figs. 28-30 were taken. 
Fig. 35. Longitudinal sections through a malpighian tube of the imago of Stegomyia 
fasciata. It is filled with liberated sporocysts. 
