CATALOGUE. 



SERIES I. 



ABNORMAL CONDITIONS IN PLANTS. 



J-HIS small series illustrates very clearly the difference be- 

 tween Variation, Dichotomy, and Homologous union, and throws 

 much light on the nature of similar malformations in the animal 

 kingdom. 



Class I. VARIATION. 



1. A Walnut with three carpels instead of two, the normal 



number. 



This is a true case of variation. The additional carpel has pre- 

 cisely similar relations to each of the normal carpels, and bears no 

 evidence of having arisen from the fission of either of these. In 

 many cases an additional part arises in plants from the develop- 

 ment of one which exists at an early stage, but which usually fails 

 by abortion. No third carpel, however, exists normally at any 

 period of development in the fruit of the Walnut. 



Presented by J. Quekett, Esq., 1859. 



2. The fruit of a Pea with three carpels instead of one. The 



third carpel is very small. There is but a single seed, 

 and this is borne by the largest carpel. 



This case differs from the former in several particulars. The 

 two additional carpels are by no means equally developed with the 

 normal one ; many of the allies of the Pea (Leguminosce) normally 

 possess three carpels, whilst the Walnut- tribe (Juglandece) either 

 have two or four. The first case is probably one of simple varia- 

 tion ; this is possibly one of reversion. 



B 



