18 ART. 3. K. ONO. 



epidermal cells, while the second from a group of cells 

 both epidermal and hypodermal. 



3. Foliar nectaries are situated on the underside of the 

 leaf, while petiolar nectaries are situated on the upper 

 surface of the petiole. 



4. Extranuptial nectaries consist of two parts : secretory 

 cells, which directly secrete the nectar on the surface 

 of the nectary ; and subglandular cells, which have 

 only an indirect relation to the secretion. 



h. External circumstances are of little importance to the 

 secretion as compared with the inner conditions of the 

 nectary itself. 



6. Among different external circumstances, moisture seems 

 to be of the greatest importance. 



7. The secretion in the case of the nectaries of the second 

 type is more active than in those of the first type. 



5. Ants are attracted by extranuptial nectaries. 



V. List of Japanese, native or cultivated plants 

 which have extranuptial nectaries. 



The names of cultivated plants are put in parentheses, and 

 those studied by myself are marked with an asterisk. 

 Polypodiaceae. 



''' Pteris aquilina L. 

 Dioscoreaceae. 



''' DiosGorea japonica T h u n b . 



''" Dioscorea Tohoro Makino. 

 Salicaceae. 



Po2^ulus balsamifera L. var. suaveolens Lond. 



''' Populus tremida L. var. villosa AVesm. 



