TEE POISONOUS PLANTS OF BOMBAY. 621 



reader, as I did in a paper published in a formar volume of this 

 Journal,* to tlie elaborate researches of Dr. John Wilson of the 

 University of St. Andrews, contributed to the pages of the '' Annals 

 of Botany,"t in an able paper entitled " The Mucilage — and other 

 glands of the PlumhagineceJ' 



Dr. Wilson describes two sets of glands, tnz. i — (1) The Mettenian 

 glands^ which in certain species of the Flumbaginece, or under certain 

 conditions, secrete chalk-scales, (2) Mucilage-glands, which secrete a 

 viscid mucilage. These glands are of two kinds :-^ (a) Stalked exter- 

 nal glands ; (b) minute internal glands which are sessile, Thase latter 

 are found on the calyx of Plumbago^ 



(J) With regard to the Mettenian glands^ Dr. Wilson observes 

 thus : — " In general, the glands occur in the longitudinal depressions 

 on the stems of plumbagos, giving rise to a striated appearance, where 

 calcium carbonate is secreted." They are present " on the leaves and 

 bracts of all, and on the sepals of many of the species " of Plumbago 

 and of other genera of the natural order Plumbaginece. They are 

 known to occur on the cotyledons of Plumbago^ ^' even before the 

 light is reached by the germinating seedlings," says Dr. Wilson. In 

 his observations on the seedlings of Plumbago zeylanica^ this careful 

 observer notes thus : — " Examples of different ages were closely exa- 

 mined, revealing the fact that no mucilage-glands exist at the base of the 

 cotyledons, Mettenian glands are as usual present on the cotyledons, 

 and they likewise occur sparingly on the hypocotyledonary axis. A 

 seedling which had the plumule destroyed at an early stage continued 

 to vegetate by its cotyledons alone, which persisted for many months. 

 They were ultimately If in. long and f in. broad, and presented tho 

 very noteworthy phenomenon of beaiing, like the leaves, chalk-scales 

 on their undersurfaoe.^' 



In my remarks on Plumbago rosea in a former number of this 

 Journal {loc. cit.)^ I candidly confessed that for a long time I did not 

 know whence came the chalk-scales or the white crust on the leaves 

 of Plumbago rosea ; I now say that the same was my difficulty in the 

 case of the white crust on the organs of Plumbago zeylanica. It would 

 be quite appropriate to observe here that even such a consummate 

 botanist as Professor Vines of Cambridge has fallen into error in tracing 



Yol. IS, pp. 345 — 365. Plumbago rosea, Linn. 

 t Vol, IV, pp. 231—255 ; 1889-1891. 



