152 Bulletin Jard . Bot. Buitenzorg, Série IH, Vol. V. Livr. 2. 



The Hausiorium. 



The présence of an haustorium or an équivalent organ is widespread 

 in the Monocotyledons. The haustorium is particularly characteristic of the 

 palms and it has served as an object for investigation for over a century. 

 Although the haustorium in its relation to germination has been known, 

 it was not until SACHS' work appeared that the real significance of the 

 whole process of germination in forms with an haustorium was understood. 

 To be sure observations on the growth of the haustorium hâve been pu- 

 blished and a pubMcation appeared in 1811 by VoiOT entitled, "Analyse 

 der Frucht und des Samenkorn von LOUIS Claude Richards". 



On pages 174 and 175 RICHARDS P'^) in describing the embryo of 

 Sclweniis Mariscus L. states the follov^'ing: 



"Unterwirft man diesen Embryo derselben Art von Analyse wie die 

 vorigen, so erblickt man gleichfalls eine Gemmula, ein Cotylédon und eine 

 Radicula. Die Keimung verândert aber die Form und die Richtung dieser 

 drei Theile sehr sonderbar. Der Cotylédon schwillt im Endosperm an ohne 

 jedoch dessen zu vergrôssern, und wird lânglich, ja gleichsam walzenformig". 

 Figures E, F, G and H show unmistakably the germination stages where 

 the haustorium (Cotylédon) enlarges at the expene of the endosperm, 



in 1866, four years after SACHS' work appeared, the plates to 

 accompany the observations of Gaudichaud {''^) were published by D. 

 Alleizette based on a voyage around the world by GAUDICHAUD in 1836 

 to 1837. In Plate 29 varions germination stages in Phytelephas Pavonii 

 are shown. hi his Figure 3 he shows the haustorium eating its way into 

 the endosperm. In the vicinity of the haustorium a dark somewhat irre- 

 gular zone is pictured. No text description of that phase is given and it is 

 very likely the zone of partially emptied cells in the vicinity of the hausto- 

 rium. A section through the neck-piece shows a radial arrangement of 

 bundles. in Figure 4 the haustorium removed from the endosperm is seen 

 as irregular ovoid body. In Figure 5 a cross section of an haustorium is 

 shown. However none of the drawings show any cellular structures. 

 Two of the stages are reproduced in Engler and Prantles', „Die Naturlichen 

 Pflanzenfamilien". 



Sachs (^') in his work on the date palm quotes from VON MOHL 

 who very cleary describes the growth of the haustorium at the expense of 

 the endosperm. This is the only known case states Sachs, where a process 

 similar to what he has seen in Plwenix dactylifera has been previously 

 described. VON MOHL (^') made his observations on Corypha frigida 

 and Phoenix dactylifera (Tab. P., Martius l.c.) 



Ebelino (') investigated besides many forms of Monocotyledons, the 

 following palms : 



Phoenix dactylifera, P, canariensis, Latania borbonica, P. tenuis, 

 P. reclinata, Seaforthia elegans, Corypha Canna and Chanuierops elegans 



