ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 195 



include the Lycopodiales and the Equisetales, and are palingenetically 

 microphyllous and cladosiphonic ; the latter include the Filicales and 

 Phanerogams, which are primitively megaphyllous and phyllosiphonic. 



Anatomical Investigation of the Leaf and of the Axis in the 

 Liparieae and Bossiaese (Tribe Genisteae).* — A. Schroeder has worked 

 out the details of the anatomy of the leaf and stem in the genera in- 

 cluded by Bentham and Hooker in these two subtribes of the tribe 

 Geuistese. These genera are characterised by simple leaves associated 

 with a marked xerophilous habit, and are natives of South Africa and 

 Australia. Leathery texture, reduction in size of blade, rolling under 

 of the margins, hairiness, and appression to the stem are notable 

 characters, while in the species of Bossieea and Templetonia the leaves 

 are reduced to rudiments and the axis becomes assimilatory. The 

 author describes in detail the characters of the epidermal cells, the 

 distribution of the stomata on the upper and lower leaf-surfaces, and 

 their position relatively to the general level of the epidermis, the arrange- 

 ment of the mesophyll, which may be bifacial or show a greater or 

 less tendency to a centric development, the character of the veins, the 

 form of the calcium oxalate crystals, and the structure of the hairs. 



As regards the stem anatomy, the author confirms the presence of 

 the characters previously indicated by Solereder for the Papilionaceee 

 as a whole, namely, simple perforation of the vessels, the constitution 

 of the ground-substance of the wood of simple-pitted wood-fibres, and 

 the relation between the pitting of the vessels and parenchyma. He 

 also notes the relative small lumen of the vessels, narrow medullary 

 rays and superficial development of cork. Presence or absence of spiral 

 thickening of the pitted vessels, and the character of the pericycle, 

 whether composed of isolated groups of bast-fibres, or forming a broken 

 or continuous sckrenchyma ring, are points of variation. 



The South Australian genus Goodia, which is exceptional in having 

 compound leaves, should, the author suggests, preferably be included in 

 the tribe Galegeae. 



Histology of the Sieve-tubes of Pinus.t — A. W. Hill has made a 

 careful investigation of the sieve-tubes of Pinus by means of W. Gar- 

 diner's methods for demonstrating cell-connections. The youngest 

 sieve-plates examined showed connecting threads like those in paren- 

 chymatous tissues. In the "boundary cells" (youngest thick-walled 

 sieve-tubes) the threads have been changed, apparently by ferment 

 action, into slime-strings, around which are formed the callus rods, while 

 at the middle lamella the median nodule encloses the nodes of the 

 slime-strings. The author describes the effect of ferment action on the 

 threads in the endosperm-walls of germinating seeds of Tamus, and 

 points out its similarity to the state of affairs in the developing sieve- 

 plates of Pinus. He has also worked out the development of the plates 

 between the albuminous cells of the medullary ray and the sieve-tubes, 

 and finds that the portions of the thread on the sieve-tube side of the 

 middle lamella undergo changes precisely similar to those described for 

 the sieve-plates, whilst the shorter portions on the cell-side of the 



* Beiheft Bot. Centralbl., xi. (1902) pp. 368-417. 

 t Ann. Bot., xv. (1901) pp. 575-611 (3 pis.). 



O 2 



