JOURNAL OF THE COLLEGE OF SCIENCE, IMPERIAL UNIVERSITY, 

 TOKYO, JAPAN. 



VOL. XXIII., ARTICLE 3. 



Studies on some Extranuptial Nectaries. 



By 



K. Ono, Rigalmshi. 



With 3 plates 



I. Introduction. 



The first systematic study ever attempted upon the anatomy 

 of the extranuptial nectary is that by FuckeP\ who took the 

 stipular nectary of Vicia sativa for his subject. Beginning with 

 the year 1875, a series of investigations on the same subject with 

 several species of plants was made by Poulsen% and since then, 

 the subject has been treated by several botanists. Among the 

 contributions on the subject in general, that of M or in i'"'^ is regarded 

 as one of the most valuable and contains some excellent illustra- 

 tions. Delpino's"*^ ^^ Fiante Formicarie'' is also a complete 

 work and treats of almost all the known cases of extranuptial 

 nectaries. In the course of these studies, the attention of botanists 

 was called to the relation of the nectary to insects and especially to 



1) Fuck el. Flora. 1845. 



2) Poulsen. Om nogle trichomer og nektaricr. Vidensk. meddel. naturli. 1875. 



3) Morini. Contribuzione all' anatomia ed alia fiisiologia dei nettaiii estranuziali. 

 Bologna, 1886. 



4) Delpino. Piante Formicarie. Bull, orto bot. Napoli. 1899, 1900, 1902, 1903. 



