376 Anatomie. 



daher möglich, dass durch diesen mit ätherischem Oel erfüllten 

 Hohlraum die zur Entwickelung des Keimlings nothwendige 

 Temperatur constant erhalten bleibt. 



Wohl steht die grosse Zahl, nicht aber das in eine be- 

 stimmte Periode der Entwickelung fallende Auftreten dieser 

 Kopfdrüsen im Einklang mit der Thatsache, dass die Samen- 

 anlagen phylogenetisch sich von Blattgebilden ableiten. 



A. Jencic (Wien). 



Sargant, Ethel, ATheory of theOrigin of Monocotyledons, 

 founded on the Structure of their Seedlings. 

 (Annais of Botany. Vol. XVII, No. LXV. 1903.) 



The seedlings of about 185 different species of Monocoty- 

 ledons were examined by the authoress, about 85 of them being 

 worked out thoroughly in detail. In the first part of the paper 

 the different types of vascular structure found in the seedlings 

 of a large number of different Liliaceae representing 35 genera, 

 chiefly belonging to the central tribes Asphodeleae, Allieae, 

 Scllleae and Tullpeae are described, and those of several species 

 belonging to the Orders Amaryllidaceae, Iridaceae, Aroldeae, 

 Palmeae and Scitamineae are also dealt with. In the course 

 of this investigation two new types of transition from stem- 

 structure to root-structure are brought to light (Anemarrhena 

 asphodelloides, Galtonla candtcans) which are different from 

 those already described by Van Tieghem. It also becomes 

 quite clear that the vascular characters of the seedling have a 

 real systematic value, and that they throw considerable light 

 Lipon the inter-relationship of the genera. By the discovery of 

 a number of intermediate forms it is shewn that the various 

 types of vascular symmetry found in the seedlings of the 

 Liliaceae can be linked up with that of the monotypic genus 

 Anemarrhena. The authoress is Ied to regard this type as 

 primitive, and as the starting point from which most, if not 

 all, the other types characteristic of the seedlings of this order 

 have been historically derived. The structure of those species 

 of the Amaryllidaceae , Iridaceae and Aroldeae that were 

 examined seems to indicate that the anatomy of the seedling 

 is to be derived from a Llllaceous type; the seedlings of the 

 Palmeae and Scitamineae, however, seem to be some-what 

 distinct in character. 



The most salient feature of the vascular symmetry of the 

 cotyledon in most Liliaceae is the absence of a midrib, although 

 such is to be found in the first foliage Ieaf. On the contrary 

 the cotyledon usually contains two main equivalent vascular 

 bundles, either alone, or with a few lateral bundles arranged 

 symmetrically with regard to both. The two main bundles are 

 often fused together by their xylems (Allium, Llltum) ; indeed 

 in the cotyledon itself this fusion is some-times quite complete, 

 but even then the double nature of the apparent midrib is evi- 

 dent in the transitional region of the hypocotyl. A dual sym- 



