294 Allgemeines. — Anatomie. — Biologie. 



ters, as shown especially by the anatomical characters. The 

 recent discovery that Lagenostoma, a seed of complex structure 

 and Cycadean type, belongs to Lyginoclendron, one of the best 

 known oi the British Cycadofihces, shows that Lyginodendron 

 was already a seed-bearing plant, ahhough in its morphological 

 characters it so closely resembles the ferns. 



The evidence thus points unmistakeably to the conclusion 

 that the Cycadophyta — the most primitive of seed plants — 

 sprang from the Fern stock. Thus the origin of the great mass 

 of Cycadean forms which overspread the world during the 

 Mesozoic period is accounted for: they were doubtless derived 

 from the more primitive Cycad-ferns of the preceding Palaeozoic 

 age, and through them from some early FiHcinean ancestry. 

 The origin of Seed-plants from the Fern phylum will probably 

 prove to hold good for other groups besides the Cycadophyta. 

 Hence, so far as the gymnospermous Seed-plants are concer- 

 ned we are led to the conclusion that they were derived, at a 

 very early period, from the Fern stock. The other great 

 problem — the origin of the angiospermous Seed-plants — is 

 as yet untouched. Arber (Cambridge). 



TUZSON, J., lieber die spiralige Struktur der Zell- 

 wände in den Markstrahlen des Rothbuchen- 

 holzes (Fagiis sllvatica). (Berichte der Deutschen Botanischen 

 Gesellschaft. 1903. Bd. XXI. p. 276.) 



Die Wände der Markstrahlzellen von Fagiis sllvatica be- 

 sitzen eine eigenartige spiralige Struktur, derart, dass beim 

 Reissen die Membran in spiralig gewundene Bänder zerfällt. 

 Bei Hölzern mit dicken, mehrschichtigen Markstrahlen scheint 

 diese Eigenschaft ziemlich verbreitet zu sein. Deutliche Spiral- 

 struktur, wenn auch nicht so auffällig wie bei Fagiis, konnte 

 Verf. nachweisen bei Platamis , Quercas, Ulmiis, Ostrya, 

 Roblnla, Allanthiis, Carplmis, Acer. Kaum wahrnehmbar ist 

 die gleiche Struktur bei Tllla, Prunus^ Fraxlniis; sie fehlt an- 

 scheinend bei Sorbits, Betiila, Alniis, Plmis und Picea. — 

 Nach Verf. trägt die Membranstruktur dazu bei, die Festigkeit 



der Zellen und des ganzen Holzkörpers zu erhöhen. 



Küster. 



Gilbert, Edward Q., „The Oxlip, Cowslip, and Prim- 

 rose". (Journal of Botany. Vol. XLI. August 1903. 

 p. 280.) 



Observations made on relations of these three plants gro- 

 wing in neighbourbood of Montreux and Villen euve. 

 Supposed crosses between P. acaulls and P. elatlor found ; 

 also crosses between P. acaulls and P. verls. P. elatlor found 

 to be more variable than either of the other species. The author 

 suggests that this variability, as also its apparent intermcdiate 

 character, may point to P. elatlor being a cross from the 



