INVERTEBKATA, CRYPTOGAMIA, MICROSCOPY, ETC. 113 



observed with certainty in the receptacles of mature organs. Since 

 these reservoirs are frequently found unchanged in the fallen leaves 

 and other deciduous parts of plants, the author considers it may safely 

 be assumed that their contents have no physiological value for the 

 life of the plant. 



Resin-passages in the Scales of the Cones of some Coniferae.*— 

 According to T. F. Hanausek, the arrangement of the resin-passages 

 in the cone-scales of some Coniferae differs from that of the resin- 

 passages in the leaves ; and he derives from this fact an argument 

 against the foliar nature of the scales. He especially notes the in- 

 variable concurrence of resin-passages and fibrovascular bundles. In 

 unison with Frank, but in opposition to Miiller, he states that it is 

 always a single cell that gives birth, by a larger or smaller number of 

 complicated px'ocesses of division, to the epithelium. The resin could 

 be detected even in the smallest intercellular spaces. He believes 

 that it is formed by the transformation of the outer lamella of the 

 cells of the epithelium. Subsequently, however, it is starch that 

 furnishes the material for the formation of resin, vanishing in the 

 winter from the scales of Biota, while the amount of resin increases 

 at the same time manifold. A different kind of resin-passage is also 

 found in the cone-scales, produced by chemical metamorphosis of the 

 cell-contents and cell-walls. 



Nectaries of Flowers, f — Towards the close of an elaborate 

 account of the variation in the structure of the nectary in different 

 flowers. Dr. W. J. Behrens thus classifies the various modes of excre- 

 tion of the nectar : — 



A. Through non-cuticularized epidermal cells of the nectary by 



diffusion. 

 a. Epidermal layer filled with metaplasm. 



a. Walls of the epidermal layer as thin as those of the other 



cells. Ranunculus Ficaria, B. pohjanthemos. 

 (3. The same ; but the secreting cells placed in the interior of 



the wall of the ovary. Agapantlms umhellatus. 

 y. Walls of the ejiidermal cells somewhat thicker than those 

 of the tissue of the nectary. Bhinanthus major. 

 h. Epidermal layer not filled with metaplasm, but with a clear 

 fluid. Alchcmilla vulgaris, Polygonum Fagojiyrum. 



B. Through thin-walled non-cuticularizcd epidermal papillae by 



difl'usiou. Dicrvilla floribunda. 



C. By the formation of layers of a mucilaginous substance in the 



cell-wall beneath the cuticle. 



a. On the whole of the epidermal layer, the cuticle being raised 



up. Nigclla arvensis. Oestrum. 



b. The same, but the secreting cells placed in the interior of 



the wall of the ovary. Scilla amuna. 



c. By the formation of mucihigo at the apex of epidermal 



papilla). Abutilon, Althtea, Tropceolum inajus. 



* ' Jahrcsb. niedcr-osterr. Landcd-uberrcalscliulo iu Krems'; aoo ' Hot. Zeit.,' 

 xxxvii. (1879; p. G95. 



t 'Fl<ira,' Ixii. (1879) p. 43.'5. 

 VOL. III. I 



