320 SUMMARY OF CURRENT RESEARCHES RELATING TO 



tion to G. Marshiana, which he briefly describes. The author believes 

 that all American types of this genus may be referred to one of three 

 species, viz. C. dacotensis, with large flowers bearing 18 to 20 micro- 

 sporophylls on a large disk ; C. Marshiana with medium-sized flowers 

 bearing 11 to 12 reduced microsporophylls, and C. nana with smaller, 

 still more reduced flowers. These three types exemplify the threefold 

 process of branching trunks, reduction of sporophylls and acquisition of 

 angiospermous seeds, which possibly characterized the process of evolu- 

 tion in Mesozoic forests. The author therefore regards the modern 

 Angiosperms as probably polyphyletic, and thinks that Gnetum is 

 possibly a non-plastic form which originated with the great races that 

 preceded the Angiosperms. Welicitschia may be a laterally related but 

 older and more stereotyped form, which would then throw light on the 

 transition from flower to inflorescence. 



Anatomy of the Sapindales.* — Ruth Holden, as a result of the 

 study of the structure of the wood of four representative genera, JEsculus, 

 Acer, Sapindifs, and Staphylea, comes to the following conclusions. It is 

 assumed, as proven from the study of the anatomy of living and fossil 

 gymnosperms, that primitive structures occur in the fibro-vascular bundles 

 of the leaf -petiole, the root, and the reproductive axis. Acer, Sapindus, 

 and Staphylea show multiseriate rays normally, JEsculus shows uniseriate 

 rays normally, but multiseriate rays in the leaf -petiole, root, and repro- 

 ductive axis. Hence it is argued that the multiseriate type of ray is 

 primitive for the Sapindales and that ^scidus is a degenerate member ; 

 and accordingly that the Sapindales rank high in any systematic ar- 

 rangement of dicotyledonous woods. 



Anatomy of the Juglandacese.f — P. Parmentier has made a very 

 complete study of the anatomic and taxonomic characters of the Jug- 

 landacefe, and maintains that while the floral structures, which have 

 hitherto been used as a basis of classification, are very uniform and 

 show few variations, the anatomic structure of laoth leaves and stem is 

 equally characteristic, and deserves at least equal consideration. 



The leaves (which are only normal at the time of the ripe fruit) and 

 the stem have short or discoid, glandular hairs, and the stomata are all 

 of the same type, being surrounded by 4-6 irregularly disposed cells, 

 and opening at the level of the epidermis. Large crystals are abundant 

 in both the palisade and spongy parenchyma of the leaves and also in 

 the parenchyma, pith, etc. of the stem. The midrib of the leaf is 

 formed of a closed bundle The periderm is sub-epidermal, while lig- 

 neous parenchyma is found in the wood of the stem. Jvglans appears 

 to have been the first representative of the family, being widely dis- 

 tributed in the Cretaceous period ; the family was much more richly 

 represented than at present. The Juglandacese appear to be derived 

 from a common ancestor which gave rise to two series, one represented 

 solely by J. reyia and the other by the rest of this genus, which in turn 

 gave rise to the remaining genera. The family appears to be most 

 closely related to the Cupuliferaj and the Myricacese. The Cupuliferse 



* Bot. Gaz., liii. (1911) pp. 50-8 (2 pis.). 



t Rev. Gen. Bot., xxiii. (1911) pp. 341-64 (4 pis.). 



