.'!<> BIOLOGICAL SOCIETY OF WASHINGTON. 



land, and America. There was some doubt until recently 

 whether the Eucalyptus really was an American type, so re- 

 mote is its present home. But during the past summer a mem- 

 ber of this Society, Mr. David White, has conclusively demon- 

 strated that these trees flourished in abundance on what is now 

 Martha's Vineyard during the Cretaceous age. They probably 

 extended over the entire western world in that vast antiquity 

 before the human race had made its appearance on our planet. 



Gamopetaly. — There was one other step to be taken, the 

 step from the polypetalous to the gamopetalous flower, from a 

 corolla consisting of numerous distinct petals forming a whorl 

 around the stamens and pistil within the calyx, to a corolla con- 

 sisting of a single piece in the form of a bell, a funnel, or a 

 tube, more and more completely protecting the essential organs. 

 The older botanies call such plants monopetalous, emphasizing 

 the fact that the corolla is of one piece, but wholly ignoring 

 the process by which it became so. In fact, by placing this 

 group after the polypetalous one they suggest that they are 

 lower in rank and that monopetalous plants may have become 

 polypetalous by division of the corolla into numerous petals. 

 The German investigators, however, have shown by embryologi- 

 cal study that the movement has been in the other direction, the 

 petals of polypetalous plants, having, as it were, united into a 

 corolla, and this is confirmed by paleobotany in showing that 

 polypetalous plants antedated monopetalous ones in the history 

 of plant development. The later botanies, therefore, so far 

 recognize this truth as to adopt the term gamopetalous to ex- 

 press this union or wedding of the petals. 



The progress from polypetaly to gamopetaly had only begun 

 when the geological record closed. Only a few gamopetalous 

 fossil plants have been discovered: There is reason to believe 

 that there were persimmons, whortleberries, olives, and arrow- 



