62 Flowers and their Unbidden Guests. 



there are many of this small size. Though these in 

 visiting the flowers would brush off the pollen, yet they 

 are kept away by the glandular hairs that stick out hori- 

 zontally from the lower and tubular part of the superior 

 calyx, because the pollen thus brushed off would be 

 completely wasted ; whereas small flying dipterous in- 

 sects, inasmuch as they flit from flower to flower in 

 rapid succession, will carry the pollen with them, and 

 transfer it to the stigmas of other flowers. 



One of the most remarkable instances of a calyx so 

 modified as to keep out unbidden guests, is presented 

 by CupJiea micropetala, H. B. K. The petals are here 

 reduced to minute lancet-shaped bodies, which are in- 

 serted on the calyx-tube at the upper extremity of 

 certain niche-like hollows, which occupy the inter- 

 spaces between the contiguous sepals. (Plate I. fig. 26 

 — a bit of the calyx-tube cut open, and showing two 

 of the lanceolate petals.) The calyx is of tubular 

 form, coloured like a corolla, 22 to 28 mm. in length, 

 and 6 to 7 mm. in breadth, has a saccular recess at its 

 base above the ovary (Plate I. fig. 28, longitudinal 

 section of flower), and secretes abundant nectar from 

 the inner surface of this recess.'^ The ovary is tolerably 

 large, is placed obliquely, and, at the point where it is 



1 The kuob-staped body, which is to be seen in this nectar- 

 cavity immediately above the base of the ovary (Plate I. fig. 28), 

 and which at first sight might be taken for a nectary, does not 

 secrete nectar, and is to be explained as an abortive carpel, through 

 the arrest of whose growth the nectar-cavity has gained in space. 



