ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 571 



through the centre of the stem and node ; (3) bundles runninp- through 

 one internode in the periphery and one in the pitli before fusing with 

 those of the leaf above. Both species have their stems, especially when 

 young, richly stored with starch, piperin and mucilage ; neither of them 

 has growth-rings. According to a recent theory the primitive angio- 

 sperms were woody, and the tendency towards herbaceous habit is 

 modern. These forms show a tendency toward elimination of secondary 

 growth and a breaking up of the woody cylinder in the following 

 characters : (1) The pericycle is broken and all that remains is a small 

 patch outside of each bundle ; (2) the interfascicular cambium appears 

 late in the internode, and still later in the nodes ; when it does occur 

 the activity is primarily on one side ; (3) there is a tendency toward 

 the scattering of the bundles in the pith. These characters, together 

 with the sheathing base of the petiole, the multilacunar type of node, 

 anastomosing of the bundles at the side, indicate a monocotyledonous 

 tendency. Moreover, the embryo-sac of the group shows the elimina- 

 tion of one division in oogenesis. 



One may conclude from this combination or characteristics that 

 P. methysficum and P. umbellatum lie in a group well toward the level 

 of Monocotyledons, and this conclusion is borne out by the female 

 gametophyte. 



Anatomy of Drimys.* — E. C. Jeffrey and R. D. Cole have made 

 experimental investigations as to almormalities in Drimys colorata, 

 D. axillaris, D. Winteri and D. aromatica. It has been found that as a 

 result of injury " peculiar tracheary structures " are developed in the 

 root. These structures appear to be abortive, and may be regarded as a 

 reversionary return of the vessels formerly found in this genus. These 

 traumatically induced structures "are characterized l)y the opposition 

 and fusion of rows of pits," thus differing from ordinary tracheides ; 

 they lack, however, the perforations of normal vessels. The authors 

 believe that in spite of tlie absence of perforation these structures give 

 indication of vessels in the ancestors of Drimys and similar forms of 

 the Magiioliaceaj. , The rays and these traumatically formed structures 

 point to the primitive position of Drimys among the MaguoliaceEe. 



Anatomy of Xerophvtic Grasses. f — E. Breakwell has studied the 

 anatomical structui'e of the grasses of Australia with special reference 

 to their adaptation to xeruphytic conditions. The present work gives a 

 brief desciption of the hal)itat, form of growth, and leaf anatomy of 

 eleven species, and the following are the conclusions based upon these 

 descriptions. Spinifex hirsvtns is specially adapted for the storage of 

 water. The hypoderma is greatly reduced, the parenchyma-cells are 

 large and colourless, aiid the xyleni-cells are very large ; on the otlier 

 hand, the epidermal cells have narrow lumens and are well protected by 

 haii'S, especially in the nei'^hhonrhood of the depressed stomata. In 

 Astrebla pertinata the hypodernia is better developed and serves to aid 

 in the mechanical strengthening of the leaf, and to repress transpiration ; 



* Ann. Bot., xxx. {j916) pp. 359-68 (1 pi.). 



+ Proc. Liijii. Sue. N. S. Wales, xl. (1!)15) pp. 42-55 (12 figs.). 



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