434 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
in the h aves and inflorescence, but differing so widely in the structure 
of the fruit that they might well be placed in different genera. 
Carpellary Venation.* * * § — M. P. Grelot points out that, in the orders 
of bicarpellary Gamopetalae, the arrangement of the dorsal and placental 
libro vascular bundles in the carpels is subject to considerable variation. 
The placental bundles, in particular, are sometimes independent in their 
whole course, and pass separately into the ovules ; while sometimes they 
unite in pairs at the summit of the ovary. 
Cotyledons of Monocotyledons.! — Dr. A. Schlickum has investigated 
the relationship between the single cotyledon and the first foliage-leaves 
in plants belonging to a number of different orders of Monocotyledons. 
When the cotyledon emerges above the soil and carries on assimilating 
functions, it exhibits also the greatest morphological similarity to a 
foliage-leaf. The chief distinctions between cotyledon and first foliage- 
leaves lie in the nature of the epiderm, in the number and mode of 
branching of the vascular bundles, to a less extent in their structure, 
and in the development of the assimilating tissue when present. When 
the cotyledon has assimilating functions to perform, its lamina displays 
a differentiation into a nutrient portion, the “ haustor ” (Sanger), and a 
conducting portion, the “ conductor ” (Leiter). In grasses the conductor 
is very rudimentary or entirely suppressed, while the haustor is trans- 
formed into the scutellum, which has no resemblance to a foliage-leaf ; 
the epiblast is here probably an outgrowth of the coleorhiza. When the 
cotyledon does not emerge above - the soil, its function is to take up,. by 
means of the haustor, the nutrient substances present in the endosperm 
or perisperm, and to protect the rudimentary leaves by the formation of 
a more or less developed cotyledonary sheath. 
Doubling of Leaves-! — Dr. L. Gabelli combats the theory that the 
tendency of a leaf to become bifid or bilobed is always pathological. 
While it may frequently be the result of injury to the growing point, it 
more often arises from the inherited tendency of the growing point to 
modify the phyllotaxis by producing more than one leaf, when favoured 
by surrounding circumstances. 
Morphology of Buds.§ — M. J. Massart classifies the leaf-buds of 
climbing plants under two heads — sarmentary , those which produce the 
long slender branches which assist the plant in climbing ( Langtrieben ), 
and those which develope into the shorter branches (Kurztrieben) which 
bear the flowers and the greater part of the leaves ; these he terms 
ramillary. Both these kinds of bud grow in rows in the axil of the same 
leaves, or, in other cases, in the axils of different leaves. In the former 
case the bud which developes first is usually ramillary, while the others 
are sarmentary. 
Accessory Buds.|| — Mr. G. EL Shull has investigated the position of 
the accessory buds in a number of woody plants belonging to different 
* Comptes Rendus, cxxii. (1896) pp. 1144-7. 
t Bibliotli. But., Heft 35, 1896, 88 pp. and 6 pis. 
X Malpighia, x. (1896) pp. 67-71. 
§ Ann. Jard. But. Buiteuzorg, xiii. (1895) pp. 121-36 (2 pis. and 1 fig.). 
|| Bot. Gazette, xxi. (1896) pp. 166-9 (1 pi ). 
