43 



its youngest stage ; and it is also a well known fact among them that the ripe 

 seed germinates very well, but no one can keep the seedlings thus obtained 

 alive for continued growth. This peculiar fact which has long remained 

 without satisfactory explanation, seemed to have recently attracted Prof. 

 SShirai's attention, as he ranked BucMeya Quadriala among parasites ; 

 but as he gave no precise account about it, I shall here set forth shortly 

 the results of my studies concerning its haustorium. The physiological 

 part of my investigation of this plant will be reserved for the future 

 paper. 



BucMeya Quadriala is a shrub widely distributed in the central part 

 of Japan. We can easily obtain in abundance its haustoria at various stages of 

 growth, as they lie comparatively shallow under ground. Besides, as they are 

 pretty large in size and are perennial, the collection of materials presents no 

 great difficulties. When we examine the root of BucMeya very carefully digged 

 out, we notice very often especially in its older part, that the haustorium is 

 placed terminally to the rootlet. This seems to be the case with the 

 perennial haustorium in general as Hein richer also found to be the same 

 with Lathraea, where he, in contradiction to Kerner's view, considered the 

 haustorium to be of the lateral origin and its terminal appearance to have 

 been caused by the decay of that portion of the rootlet which would lie 

 beyond the haustorium. I could confirm his view in the case of BucMeya 

 by studying the haustoria at different stages : while the young one still 

 retains on its top a slender portion of the rootlet, the older one often loses 

 it, the connecting point however being easily distinguishable on account of the 

 presence of the scar or small process upon the haustorium. 



The young haustorium exhibits so close resemblance in its structure with 

 the same organ of Thesium that it is hardly worth while to describe it here 

 in detail. The contact surface of the haustorium of BucMeya is furnished 

 with a few pairs (generally two or three in number) of attaching folds 

 (Anheftungsfalten), as we find in Thesium when it attacks the root of a 

 monocotyledonous plant. 3) The only distinction between the two is that 

 in BucMeya the outer or older pair is always larger than the inner e*^~ 



l)Shirai, Plant-Disease. Vol. II, 1894. (Japanese). 



2) Heinricher, Biologische Studien an der Gattuug Lathraea. Ber. d. deutscb. hot. 

 Gesellsch. Bd. XI, 1893, p. 9. 



3) Compare the figures of Thesium-haustoria in Pitra's Ueber die Anheftungweise 

 einiger Phanerogamen Parasiten an ihre Nahrpfianzen (Bot. Ztg. 1861) and Graf zu Solms- 

 Laubach's Ueber den Bau und die Entwicklung der Ernahrungsorgane parasitiseher 

 Phanerogamen (Jahrb. f. wiss. Bot. Ed. VI, J 867-1868). 



