INTERCELLULAR SECRETORY RESERVOIRS. 209 



that described for the group of the Rutacese. Their origin, judging from observations 

 described, can hardly be other than that stated by ^Martinet, viz. lysigenetic, though 

 Franic describes it as schizogenetic. Cavities of the same sort occur in the superficial 

 parenchyma of the cortex of the stem. In those of the stem of Hypericum balearicum 

 Unger ^ found papillose and hair-like processes rising from the wall into the cavities. 

 Many species of Hypericum, e.g. H. calycinum, canariense, hircinum, &c., have no 

 transparent spots recognisable with the naiced eye : it is uncertain whether the oil- 

 cavities are absent in these cases, or, more probably, are only smaller than in the punctate 

 species, or are in some way hidden. 



{d) The bodies scattered in the parenchyma of species of Hypericum, which contain 

 violet colouring matter, and are described by the above authors as glands, may here be men- 

 tioned, and recommended for further research: also the similar bodies in Gossypium. 

 In the leaves of some species of Hypericum, these consist of spherical, loose aggregates 

 of round cells ; the colouring matter apparv^ntly lies between them. In the leaves of 

 Gossypium they are round, undoubtedly lysigenetic cavities, which are filled with the 

 violet colouring matter, soluble with difficulty in alcohol. 



{e) Among the Myoporeae the species of INIyoporum have numerous round oil-cavities 

 of unequal size in the leaves and the outer cortex of the branches. The cavities are 

 superficial, and separated only by one or two layers of cells from the epidermis, which is 

 arched convexly outwards, e. g. M. parvifolium : in M. tuberculatum, on the contrary, 

 according to Unger ', they occur in the middle of the chlorophyll-parenchyma of the leaf. 

 They are surrounded by 1-3 layers of flattened cells. As far as investigated, their origin 

 appears to be lysigenetic. 



{f) In the parenchyma of species of Lysimachia, of Myrsine africana, and Ardisia 

 crenulata a resinous body is found in intercellular spaces ; it is soluble with difficulty in 

 alcohol, easily soluble in ether, of a bright brownish red colour, and forms fixed, often 

 almost brittle masses : its chemical properties require closer investigation. Its mode of 

 distribution differs in special cases, and of those plants investigated it is simplest in 

 Lysimachia Ephemerum. In the root of this plant it appears in most of the usual 

 prismatic, air-contaii.ing, intercellular spaces as a finely granular covering on the wall of 

 the adjoining cells : here and there it is interrupted, while in thickness it varies from that 

 of an insignificant layer to such a bulk as to fill up the passage. In the very lacunar 

 parenchyma of the pith and cortex of the stem, it has fundamentally the same distribution, 

 but is less regular, owing to the irregular form of the cavities : in neighbouring cavities it 

 is contained in very unequal quantities, in many not at all. When secreted in quantity, it 

 forms on the cell-wall a convex covering, striated perpendicular to its surface. Finally, 

 it is found in the leaves, in the cavities of the chlorophyll-parenchyma, as thick, irregu- 

 larly shaped masses, with indistinct radial striation : the cavities are surrounded some- 

 times by ordinary ceils, sometimes by a more or less distinct layer of flattened cells. 



The secretion is strongly localised in the leaves and the cortex of Lysimachia 

 punctata ^ and of Myrsine, in the leaf of Ardisia, and of most Lysimachias. Here round 

 reservoirs, which appear as points to the naked eye, are found in the parenchyma : they 

 are surrounded by about eight flat, closely connected, chlorophyll-containing cells, and 

 filled with the dense red secretory body, which is in Myrsine radially striated in a remark- 

 able way. The reservoirs arise schizogenetically, and contain the secretion as soon as 

 they are visible. In the cortex of branches of the above Ardisia, the reservoirs are 

 rarely round, usually elongated, spindle-shaped, appearing as little strokes more than 

 jmrn ill length. 



In the roots of Lysimachia vulgaris and punctata, and of Myrsine, the secretion does 

 not lie in intercellular spaces, but in single sacs or cells, not distinguished in size or form 

 from the surrounding cells of the parenchyma : in each of these there is a body of the 



^ Anatomie und Physiologic, p. 213. 



^ P. Moldenhawer, Beitr. p. 162. — Meyen, Secretionsorgane, p. 61. 



