160 A NEW ZEALAND NATURALIST'S CALENDAR. 



Zealand these flowers are usually dioecious, while here they 

 possess both stamens and pistil. Yet though structurally 

 hermaphrodite, they are functionally unisexual, and I do 

 not think they can set seed without the intervention of 

 insects. The black mapau (P. tenui folium) has always, 

 apparently, perfect flowers, yet it is probably quite incapable 

 of self-fertilisation ; its near ally, P. Buchanani, from the 

 North Island, certainly is. The black mapau differs remark- 

 ably from the white in having much larger solitary flowers, 

 which are bright reddish purple when they first open but 

 which become very dark before withering. They also 

 possess the nectar beads, but are not apparently fragrant. 

 The difficulty in ascertaining how these flowers were 

 formerly fertilised is that so many of the native insects 

 which used to do this work are now nearly exterminated 

 by introduced birds, so that the original conditions have 

 been very much altered. I have no record of any insects 

 observed on them except hive-bees. 



One of our commonest mistletoes, Tupeia antarctica,* 

 a leafy parasite of a rather pale green colour, flowers this 

 month. Its flowers are yellowish-green in colour and are 

 completely dioecious, the staminate and pistillate forms 

 being found on different plants. Thoiigh so inconspicuous 

 they are very fragrant, and secrete a large amount of 

 nectar. I have noticed that they are much frequented by 

 midge-like flies, which in sucking the nectar from the flat 

 discs of the blossoms bring the lower part of their bodies 

 into contact with the stamens and stigmas. 



While still too early for most native flowers, the follow- 

 ing are to be met with in September: Melicytus lanceolatux, 

 a large-leaved kind of hina-hina, still common enough in 

 the West Taieri bush and formerly to be met with in the 

 wooded gully of the Wakari Creek passing through the 

 golf links. It differs from the common hina-hina, which 

 flowers later in the season, in being functionally dioecious. 

 Astelia nervosa, a common liliaceous plant in the bush, 



* See page 127. 



