402 Anatomie. 



ming sheaths around the xylem and phloem groups, which are 

 radially arranged in each Strand with exarch protoxylems. In 

 this region, therefore the ground parenchyma of the root is 

 traversed not by a Single vascular cylinder alone, but by a series, 

 each with a root-like structure. The endodermis may sometimes 

 be seen as an incomplete ring around the externa! surface of 

 the more peripheral Strands or cyHnders. Passing outwards 

 the more peripheral cylinders first of all fuse laterally to form 

 a series of incurved arcs (as seen in transverse section), then 

 by progressive fusion the number of free Strands becomes 

 successively reduced, and a more or less complete ring is 

 formed, At the same time the internally orientated groups of 

 xylem and phloem gradually disappear. The ring remains in- 

 complete longest on the adaxial side, but eventually a simple 

 central cylinder of normal root structure is established. 



In most cases all these changes are completed in that 

 portion of the root which is enclosed in the cortex oi the stem, 

 but in Kentla sp., Areca sp., Areca Catechii, Areca concinna, 

 Dypsis madagascarensis, and Iriartla sp., the structure with 

 the separate Strands is continued into the extracauline free 

 portion of the root for about a foot or more. 



Other Palm roots are also described in which it appears 

 that traces of the basal structure also persist in the free region 

 as medullary Strands of xylem or phloem. In Areca concinna 

 the departure of a lateral root leaves a gap in the vascular 

 ring of the main root, and the cylinder of the lateral root it- 

 self is incomplete on the adaxial side at its base. 



In discussing his results the author comes to the conclusion 

 that all ideas of „monostely" and „polystely" and of „medulla" 

 and „cortex" as separate morphologica! entities are founded 

 upon an artificial conception of the nature of the structures 

 involved, and that in both stem and root we have to deal with 

 a common parenchymatous ground-tissue through which run 

 Strands of xylem and phloem, usually accompanied by fibrous 

 tissue, often in the form of sheaths. d. J Gwynne-Vaughan. 



Eberlein, L., Beiträge zur anatomischen Charakte- 

 teristik der Lythraceen. (Dissertation Erlangen. 1904. 

 %\ 78 pp.) 



Die Hauptresuitate seiner gründlichen und umfassenden 

 Untersuchung der Blattanatomie der Lythraceae fasst Verf. in 

 der Einleitung der vorliegenden Arbeit folgendermassen kurz 

 zusammen: Die bisher nur bei einem kleineren Theil der 

 Lythraceen-Gaitungen und nur in der Achse constatirten bicol- 

 lateralen Gefässbündel finden sich bei allen vom Verf. unter- 

 suchten Gattungen und Arten auch in den grossen und grösseren 

 Nerven. Sehr verbreitet ist das Auftreten einer verschleimten 

 Blattepidermis, obgleich die Lythraceae grossentheils an feuchte 

 Standorte gebunden sind. Die Spaltöffnungen folgen rücksicht- 



