154 Miscellaneous. 



of iodine. I therefore conclude, in the case of Knautia arvensis, 

 Coulter, that the nectary is a small cylinder under the style, and in 

 Succisa pratensis, Mcench., that it is a very peculiarly loose accumu- 

 lation of cells at the base of the corolla, under the greatest lobe ; and 

 I arrive at this conclusion because these parts are coloured the most 

 darkly by iodine, and because their structure is analogous to that of 

 nectaries in general. 



With respect to the contents of the cells of the nectary, we must 

 carefully distinguish between the contents of the common cells and 

 those of the pores. The contents of the former usually consist of a 

 yellowish, greenish or uncoloured, transparent juice, and of a gra- 

 nular matter, the grains of which are sometimes so small that they 

 are scarcely visible, even with a magnifying power of 550, the whole 

 having the appearance of a mass of slime interspersed with traces of 

 grains. In most cases however the grains are clearly visible. Their 

 colour varies considerably, but is limited to the different shades of 

 yellow, green, gray, brown, and obscure violet, though the last is but 

 very rarely observed. It did not occur once in the two hundred 

 plants I examined last year. The colour of the grains is generally 

 the most readily detected when they are congregated one upon the 

 other in small clusters. The individual grains are generally colour- 

 less and transparent. Sometimes in addition to the above-mentioned 

 grains there are very large grains of the same globular form, but 

 entirely transparent and free from colour, as in Pedicularis palus- 

 tris, L. I need hardly mention, that there are also in the nectaries 

 of plants, crystals, air-vesicles, &c, which have no reference to the 

 present subject. 



The grains contained in the cells of the nectary are also in most 

 cases coloured yellow or brown by iodine. 



In eleven plants iodine obviously colours the grains blue, and thus 

 proves that they are starch. In four others it colours them a bluish- 

 brown or a brownish-blue : Armeria maritima, Willd., Hyoscyamus 

 niger, L., Hypocharis radicata, L., and Sinapis alba, L. The eleven 

 plants the grains of which become blue by the application of iodine 

 are the following : Pedicularis palustris, L., Arenaria media, L., 

 Mentha arvensis, L., Malva moschata, L., Malva sylvestris, L., Cli- 

 nopodium vulgare, L., Convolvulus sepium, L., Conv. arvensis, L., 

 Lychnis sylvestris, Hoppe, Lychnis dioica, L., Bryonia dioica, L, 

 In the nectary of Pedicularis palustris only the above-mentioned 

 larger and transparent grains take the blue colour. The nectary 

 of Arenaria media, L., is the base of the sepals, where they abut 

 upon the filaments, and the epidermis only contains starch. The 

 nectaries of Lychnis sylvestris and dioica are on the gymnophorum 

 between the bases of the petals and their processes. In Lychnis 

 sylvestris I found evidence of starch only in the male flower, and in 

 L. dioica only in the female flower. The grains of starch vary very 

 much in size. The diameter of the largest is only about one-fourth 

 of the diameter of a common grain of potato -starch, and the smallest 

 grains are scarcely visible even with a magnifying power of 550. 

 The form of the grains is irregular, but more or less globular. Though 

 coloured by iodine they remain transparent, and generally show a 



