Meyen's Report for 1839 on Physiological Botany. 135 



^scovery in a letter to M. Mirbel in August 1830, and this 

 letter has been used by M. Brongniart, although the observa- 

 tion is rejected. [The presence of stomata in the hairy pits 

 of the Nerium leaves was first published by M. Krocker, jun. 

 of Breslau, in his dissertation ' De Epiderraide Plantaruna/ 

 1833.— Mey.] 



M. Morren* has examined anatomically several species of 

 Hedychium, and has recorded his observations and accom- 

 panied them with figures. We receive information concern- 

 ing the cells and their contents both in young and old leaves, 

 as also on the occurrence of crystals in these different ages of 

 the species of Hedychium ; also several forms of crystals are 

 mentioned as having been observed in these plants. 



On the walls of the air-cells M. Morren found peculiar cells 

 which were provided with green-coloured sap-globules, were 

 of various forms, but very often corniform and hamate, some- 

 times symmetrical, sometimes umsymmetrical ; they are said 

 to be similar to the stelliform hairs of the Nymjjhcea, in which 

 however I cannot agree, for these cells are nothing else than 

 more or less regularly formed stellar-shaped cells, as they 

 generally occur in the Scitaminea. M. Morren also thinks 

 that he has found that evaporation does not assist the forma- 

 tion of crystals in plants, inasmuch as it is exactly in the dry 

 and peripheric parts of plants that crystals are not found. The 

 other communications only confirm that which had been here- 

 tofore obsei'ved in Hedychium, or in other similar plants. 



From M. Morren t we have received a similar work on the 

 genus Musa : in it the formation of the stellar-formed cellu- 

 lar tissue is fully described, and some remarks are made on 

 the acicular crystals found in the Musce and other plants. 

 The observations on the formation of the above-mentioned 

 tissue confirm my former statements, viz. that those cells are 

 produced from ordinary parenchym-cells. M. Morren saw 

 the molecular motion in several cells oi Musa, and after he 

 had observed single parts of the plant in different stages of 

 development, he arrived at the conclusion, that substances in 

 the interior of the stellar-shaped cells make their appearance 

 in the following order : — first appear self-moving gum or fe- 

 cula-globules, then motionless chlorophyll [i. e. globules co- 

 loured by chlorophyll, Mey.), and then free globules and cry- 

 stals : all these matters are formed successively. When 

 considering the crystals which are found so frequently in the 



* Bull, (le rAcnd. Royale de Bruxelles, t. vi. no. 2. 

 t Observations sur I'Anatoniie de Musa. — Bullet, de I'Acad. Roy. dc 

 Bruxelles, t. vi. no. .3. 



