STUDIES OX SOME EXTKANUPTIAL NECTAKIES. 13 



TJie second type, 



Div. I. Pruniis yedoensls ; P. macrophylla ; P. Laurocerasus ; 

 Aleurites cordata ; Excoecaria japonica ; Mallolus jjapo- 

 nicus ; Sapium sebiferum ; Merculiaris leiocarpa ; Idesia 

 p)olycarpa ; Popmliis tremula var. villosa. 



Div. II. 



a. Luffa cyUndrica. 



h. Cassia sulfur ea ; G. occidentalis. 



c. Viburnum dilatatum ; V. Opiilus ; V. jap>onicum ; 



Diospyros Lotus; D. morissiana ; Impatiens balsamina; 



Ailanthus glandulosa ; Sambucus racemosa. 



E. Secreting season. 



April : Sambucus racemosa ; Prunus yedoensis ; Viburnum 



dilatatum ; V. japonicum ; Vicia faba. 

 May : Vicia saliva ; Primus persica ; P. communis ; Excoecaria 



japonica ; Sapium sebiferum ; Viburnum Opulus ; Idesia 



polycarpa ; Sterculia platanifolia ; Polygonum sachalinense ; 



P. cuspidatum forma 3Ieigetsuso ; Syringa vulgaris ; S. 



amurensis var. villosa. 

 June : Aleurites cordata ; Hibiscus tiliaceus. 

 September : Urena sinuata ; Cassia sulfurea. 

 October : Luffa cylindrica ; Osmanthus aquifolium. 



Each nectary has its own secreting season, and in most cases 

 the secretion lias certain relations to the flowering season. Some- 

 times the secretion occurs simultaneously with the development 

 of the young slender leaves. 



III. Physiological experiments. 



For the secretion of the nectar, the external circumstance 



