2 ART. 10. — S. KUSANO : STUDIES ON THE PARASITISM 



Tt must therefore bo admitted that studios on the ecology and 

 physiology of these plants, interesting and important as they 

 are, are still wanting, whereas about the habits of hemiparasites 

 belonging to other families we have a more or less clear knowledge, 

 owing to the numerous investigations of Koch, 1 ' Peirce, 2) Hein- 

 riciier/ Wettstein, 4) etc. 5) ; for instance, the gradation of ac- 

 commodation from autophytic towards parasitic nature was found 

 to prevail among several kinds of plants in a certain family. 

 So far as the Santalacea? are concerned, the results obtained up 

 to the present time are, as already indicated, very meagre, and 

 leave much to be desired, especially on the mutual relations 

 between the host and the parasite. 



With the view of throwing some light upon this subject, T took 

 up Buchleya Quadriala for study, as this plant is easily accessible 

 to us. It will be proper to give first an account of its parasitic 

 nature and then to proceed to the structure of its haustorium. 



] ). Koch, Ueber die directe Ausnutzung vegetabilischer Reste, etc. Ber. d. deutsch. hot. 



Gesellsch. Bd. V, 1S87, p. 350 ; , Zur Entwickelungsgesclücbte der Ehinanthaceen. I. Rhin- 



anthus minor Ehrh. Jahrb. f. wiss. Bot. Bd. XX, 1889, p. 1 and II. Euphrasia officinalis L. 

 Jahrb. f. wiss. Bot, Bd. XXH, 1891, p. 1. 



2). Peirce, On the Structure of the Haustoria of some Phanerogamic Parasites. Ann. 

 of Hot. Vol. VII, 189::, p. 291. 



3). Heinricher, Die grünen Halbschmarotzer. I. Odontites, Euphrasia und Orthantha. 

 Jahrb. I', wiss. Bot. Bd. XXXI, 1898, p. 77; II. Euphrasia, Alectrolophus und Odontites. 

 Jahrb. f. wiss. Bot. lid. XXXII, 1898, p. 3S9; III. Bartschia und Tozzia, etc. Jahrb. f. 

 wiss. Bot. Bd. XXXVI, 1901, p. 665; IV. Nachträge zu Euphrasia, Odontites und Alectro- 

 lophus. Jahrb. f. wiss. Bot. Bd. XXXVII, 1902, p. 264; , Zur Entwickelungsgeschichte 



einiger grüner Halbschmarotzer, (Vorl. Mittheil.). Ber. d. deutsch. Bot. Gesellsch. Bd. XVII, 



1^'.)'.>, p. (244); , Auf dem Wege vom Halbparasitismus zum absoluten Parasitismus. 



Sond. Abdruck aus Ber. d. naturwiss-ruedicin. Vereins in Innsbruck. XXV, 1899/1900. 



4). Wettstein, Monographie der Gattung Euphrasia. Leipzig 1896. 



5). BONNIER, <i., Sur l'assimilation des plantes parasites à chlorophylle. Comptes rendus. 



Bd. 11.".. 1891; , Recherches physiologiques sur les plantes vertes parasites. Bull. d. 1. 



soc. bot. d. France et d. 1. Belgique 93, p. 77 : Cannon, AV. A., The Anatomy of Phora- 

 dendron villosum Nutt. Bull, of the Torrey Bot. Club. vol. 28, 1901, p. 374; Volkart, A., 

 Untersuchungen über den Parasitismus der Pedicularis- Arten. (Inaug.-Diss.). Zürich 1899; 

 Spf.rj.tch, A., Beiträge zur Kenntniss der Inhaltsstoffe in den Saugorganen der grünen 

 Rhinanthaceen. Beihefte z. Bot. Centlbl. Bd. XI, 1902, p. 4:'.7. 



