464 ON THE ORGANS OF SECRETION IN THE HYPERICACER. 
upon, and finally they are obliterated in the same way as those 
described above as occurring in the fundamental tissue. 
The results of my observations I may summarize briefly thus :— 
' 1l. The view advocated by Link, Martinet, and De Bary of the 
lysigenous origin of the reservoirs of ethereal oil in these plants 
is the correct one. 
2. There exists in many parts of the plants a series of ducts 
or passages differing only slightly from these reservoirs; the 
differences being that they are not globular and isolated, but 
are generally connected more or less intimately with each other, 
and that their secretion is not a clear ethereal oil but a viscid or 
resinous liquid ; the points of agreement being those connected 
with their development and function. 
3. At least in some species, there is also a series of schizogenous 
ducts confined to certain portions of the phloém. 
4. The dark glands whieh have been described are in intimate 
relationship with the fibrovascular system. ; 
5. The formation of resin and kindred secretions in these 
plants is confined to the parts where metabolism is active and 
where there is a primary meristem. That all such parts give 
evidence of such formation with the exception of the roots. 
EXPLANATION OF THE PLATES. 
Puate XXXIX. 
Figs. 1-8. Showing development of resin-passage in the stem of Hypericum 
calycinum. : 
Fig. 9. A longitudinal section of portion of the stem of H. calycinum, with 
resin-passage about the same stage as in fig. 4. 
Figs. 10-12. Showing development of glandular body in the leaf of Hypericum 
tetrapterum. 
Figs. 13 & 14. Similar development observed in the leaf of H. calycinum. 
Figs. 15 & 16. The same in leaf of Hypericum hirsutum. 
Fig. 17. Longitudinal section of the dark gland in H. hirsutum. 
Pare XL. 
Fig. 18. Longitudinal section of the passages in ovary of Hypericum calycinum. 
Fig. 19. Part of the same, more highly magnified. 
Fig. 20. Transverse section of the ovary of H. calycinum, showing the final 
state of the passage. 
Fig. 21. A transverse section of a passage in the ovary of H. tetrapterum. 
Fig. 22. Young gland in the leaf of Hypericum balearicum. 
Fig. 23. Showing the mature dark gland in the leaf of Hypericum Lee 
Figs. 24-28. Illustrating the development of the passages in the bast of stem ° 
Hypericum calycinum. 
