250 Vnrii'ties and Morphology of the IJuman Lachrymal Bone. 



l.i. ]>n nial bone ; /=- section of nasal process of maxilla ; #- section of nasal bones ; 

 A "lumen of lachrymal sac. 



4. Lachrymal region of fifth month foetus. 



5. Ibid., fourth month. 



6. Ibid., seventh month. 



7. Ibid., eighth month. 



9. Lachrymal bone of eleventh week, outline. 



10. Lachrymal region of adult, with ossiculum maxillo-frontale. 



11. Ibid., with four os&icula coexisting. 



12. Coexistence of ossic. hamuli and o. canalis. 



13. Ibid., with large o. ethmo-lachrifmale superior with o. hamuli and o. canalit. 



14. Ibid., with very large o. hamuli encroaching on maxilla. 



15. Ibid., o. hamuli and o. canal U both separate from lachrymal. 



16. Ibid., o. canalift coexisting with hamulus and peculinr form of mtura notha. 



17. Ibid., o. hamuli with vascular hole between it and lachrymal. 



18. Ibid., with o. ethmo-lachrymale inferior. 



19. Ibid., o. hamuli ankylosed to nasal process of maxilla, o. canalis, to orbital 

 plate. 



20. Absent lachrymal bone, replaced by backward extension of nasal process of 

 maxilla (r), between which and the upward extension of the inner portion of the 

 orbital plate is the suture (y). There is an ossiculum canalis with a very small 

 lueuna above it. 



21. Well-marked suturn notha, small o. hamuli turned into the canal. 



22. Double lower end of sulura notha, foraminated lachrymal groove and small 

 o. canalis. 



23. Small o. ethmo-lachrymale superius occupying the entire region of the ethmo- 

 lachrymal suture ; rnaxillo-lachrymal suture ankylosed. 



24. Persistent vertical suture and o. canalis. 



25. O. maxillo-frontale. 



26. Arrangement of ossicles and sutures, with vascular foramina. 



27. Inner surface of lachrymal bone, showing its relations to lachrymo-ethmoirlal 

 cells (. /. c. and t. /. c.) and antrum (a), i. = infundibulum ; m. /. = maxillo- 

 turbinal. 



28. Case of deficient lachrymal, with small lacuna and no ossicle. 



