Mr. G. Lawson on Cinchonaceous Glands in Galiacese. 163 



is surrounded by a .layer of much more elongated obconical, 

 somewhat prismatic cells, which are closely set around the nu- 

 cleus in a radiant manner, lying upon it like achenes upon a 

 conical receptacle. 



These elongated cells are described by Weddell as having, in 

 the centre of the outer extremity or apex of each, a minute canal 

 or perforation in the cell-wall, communicating with the interior 

 of the cell, and serving to discharge the secreted fluid. This he 

 says is particularly evident in Cinchona Calisaija; and the Com- 

 mission appointed by the Academy of Sciences to report upon 

 Dr. WeddelFs investigations (MM. Richard, Gaudichaud and 

 Jussieu) specially drew attention to the circumstance, as of rare 

 occurrence in vegetable glands. 



I have not been able as yet to demonstrate the canal satisfac- 

 torily, although the glands of Cinchona Calisaya, and of other 

 species, have been carefully examined with this view. But, by 

 this expression of my own failure to see what no doubt requires 

 a combination of favourable circumstances, supplemented by 

 patient examination, I do not mean to impute error of obser- 

 vation to so excellent an observer as Dr. Weddell ; and refrain, in 

 the meantime, from entering upon a discussion of the point, as 

 it has specially occupied the attention of my friend Dr. John 

 Kirk, whose researches I trust will ere long be laid before the 

 Botanical Society. It may here, however, be remarked, that the 

 secretion is certainly discharged from the apex of the elongated 

 cells forming the outer layer of the gland, and under certain cir- 

 cumstances appears in the form of minute globules on their sur- 

 face. It is not likely that such globules were taken by Dr. Wed- 

 dell for canals, but they have sufficiently that appearance to be 

 mistaken by an inexperienced observer. 



In size and form the glands vary considerably in different 

 species. In Cinchona Calisaya they are of an ovato-lanceolate 

 form, and measure ^^^yth of an inch in length by y\jth in breadth j 

 while in Ixora coccinea they are very much attenuated, of a linear 

 lanceolate form, and measure ^^(jth of an inch in length by only 

 g^j^th in breadth. 



In occasional cases, though rarely, two glands are found in 

 adhesion. 



These stipular glands have been hitherto regarded as quite 

 peculiar to the Natural Order Cinchonacece, and have been em- 

 ployed as a character whereby to distinguish that order from 

 Galiacea, in which their presence has not hitherto been suspected, 

 or has rather by implication been denied. 



I have recently ascertained, however, that the so-called Cin- 

 chonaceous glands are by no means limited to Cinchonacea. 

 They likewise occur in the Galiace(je, and I believe that the 



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