Band 140. Nr. 12. XL. Jahrgang. I. ßd. Nr. 12. 



Botanisches Centralblatt. 



Referierendes Organ 



der 



Association Internationale des Botanistes 

 für das Gesamtgebiet der Botanik. 



Herausgegeben unter der Leitung 

 des Präsidentelt: des Vice- Präsidenten : des Secretärs: 



Dr D. H. Scott. Prot. Dr. Wm. Trelease. Dr. J. P. Lotsy. 



Und der Redactions-Comi^K issions- Mitglieder : 



Prof. Dr. Wm. Trelease, Dr. C. Bonaventura, A. D. Cotton, 



Prof. Dr. C. Wehmer und Mag. C. Christensen. 



von zahlreichen Specialredacteuren in den verschiedenen Ländern. 



Dr. J. P. Lotsy, Chefredacteur. 



Abonnement für das halbe Jahr 25 Mark 

 No. 12. durch alle Buchhandlungen und Postanstalten. 



1919. 



Alle für die Redaction bestimmten Sendungen sind zu richten an: 

 Redaction des Botanischen Centralblattes, Haarlem (Holland), Spaarneiy. 



Davie, R. C, A Comparative List ofFern Pinna-traces, 

 with some Notes on the'Leaf-trace in the Ferns. (Ann. 

 Bot. XXXII. p. 233—245. 5 text figs. 1918.) 



This memoir forms a continuation of the author's previous work 

 on the anatomy of Fern-leaves (Ann. Bot. XXVI. p. 245—268; Trans. 

 Roy. Soc. Edinb. L. p. 349-378 and LH. p. 1—36). The results 

 obtained by the investigations detailed in these four papers may be 

 summarized as foUows: 



There are two types of pinnasupply from the leaf-trace in the 

 Ferns. In the 'extra-marginal' type, the portion of the pinna-trace 

 which comes from. the adaxial side of the leaf trace is nipped off 

 from the back of a 'hook', technically from the abaxial face of the 

 curved leaf-trace; the extreme top of the adaxial portion of the 

 leaf-trace is continued upward as part of the leaf-trace. In the 

 'marginal' type, the adaxial portion of the leaf-trace (nearest 

 to the pinna) is itself given off to supply the pinna. A tabular 

 scheme of the distribution of the two types of pinna-supply in the 

 Ferns has been drawn up; among the Ferns examined, the extra- 

 marginal type occurs in 46 genera with 94 species, the marginal 

 type in 51 genera with 126 species. With a few exceptions, the 

 rule holds that the same type of pinna-supply is found in the spe- 

 cies of a genus of Ferns recognized as such in Christenscn's 

 'Index Filicum'. In order to make use of the criterion of the type 

 of pinna-suppl}-- in the Ferns, the lower pinnae of the older leaves 

 must be examined. Agnes Arber (Cambridge). 



Sharples, A., The Laticiferous System oi Hevea bvasitiensis 



Botan. Centr.-ilblatt, Band 140. , 19 9. 12 



