436 Mr Berwick's Observations on 



Observations on Glands in the Cotyledons, and on the Mineral 

 Secretions of Galium Aparine, L. By Thomas Berwick, 

 University of St Andrews. Communicated by Dr 

 John Wilson. (Plate III.) 



(Eead 13tli February 1890.) 



In a paper read before this Society Professor Lawson says 

 that " In Galiacem the glands occur apparently in the axils, 

 but in reality in the inner or upper surface of the bases of 

 the leaves. In structure they bear a considerable resem- 

 blance to the stipular glands of many Cinchonacem, with 

 this difference, however, that they are generally either dis- 

 tinctly stipitate, or club-shaped ; whereas those of Cinchonacece 

 are usually thickest at the base, and taper (more or less 

 gradually in different species) towards the apex. When 

 stipitate, the stalk of the galiaceous gland is composed of 

 two or three (sometimes more) series of cells, those running 

 up the centre sometimes containing green chlorophyll 

 granules ; none of these, however, being usually exhibited 

 in the body of the gland." * His excellent paper deals with 

 the glands of the leaf whorls, but it is the development of 

 the cotyledonary glands which we shall now consider, of 

 which no notice, so far as I am aware, has been taken. The 

 plant examined with this object was Galium Aparine. 



With reference to glands in cotyledons, however, Dr John 

 Wilson informs me that he detected mucilage glands in the 

 axils of the cotyledons of Statice and Armeria, but that they 

 did not occur in all genera of the Plumhaginem. 



In Galium Aparine they occur in the axil of the cotyle- 

 dons, just as the above author describes them as occurring in 

 the stipules and leaves composing the whorls. I detected 

 two glands in an embryo (I'late III., fig. 1), dissected out of a 

 seed which had lain in the soil, but no germination had 

 taken place, and the albumen was still quite horny ; these 

 glands were in the axil of the cotyledons. Another embryo 

 dissected out of a seed which had lain in the soil rather 

 longer, but in which likewise no germination had taken 

 place, had also two glands in the same position. On staining 



* Trans. Bot. Soc. Edin. (1856), vol. v., part i., p. 6. 



