154 Thiselton-Dyer. — Morphological Notes . 
VI. Abnormal Fruits. — Pleiotaxy of Gynaeceum 
in Orange. 
I was indebted to a correspondent for the abnormal orange 
figured in Plate IX. As is well known, the fruit of the 
orange ordinarily consists of a single row of carpels enclosed 
in a fleshy rind. In this case the axis has been prolonged 
and has given rise to another series of carpels forming 
a smaller fruit, which is entirely immersed in the external 
one. Although various abnormalities in the fruit of the 
orange have been figured, I have been unable to find any 
illustration of a similar one. Masters (Teratology, p. 75) 
figures a case in which the outer united whorl surrounds 
a confused mass of free carpels. A similar case is better 
figured by Risso and Poiteau (Histoire et Culture des 
Orangers, tab. 56). 
A similar state of things to that now described is said to 
be characteristic of the so-called ‘ Californian Navel Orange.’ 
This apparently originated as an isolated sport, as the trees 
in California are said to have been all propagated from one 
which is still preserved at Washington. 
A. P. de Candolle regarded the ‘ rind ’ of the orange as 
developed frqjn the torus or receptacle, which is usually 
regarded as an axial structure (Organographie, vol. ii. p. 41), 
and Masters (Teratology, p. 75) favours this view. 
In tire case now figured (Fig. 4) the external rind had been 
removed before it came into my hands. The carpels are 
united below to the prolonged axis, but are separated above 
to leave an open pit, at the bottom of which is the secondary 
fruit. The ventral surface of the carpels is clothed with the 
characteristic glandular c rind.’ This is shown in section in 
Fig. 5, where the glands are unusually prominent, and crowded 
together in groups with little intervening tissue. In such 
a position the ‘ rind ’ could hardly be an axial structure. The 
secondary fruit is shown in section in Fig. 6 ; except that 
