The development of the ovule, embryo-sac and egg in Podostemaceae

During my voyage to the West-Indies I had an opportunity of visiting in Surinam some of the rapids where Podostemaceae grow, namely the Armina falls of the Marowyne river. There I collected material of these remarkable plants, and at a later date I received an abundant supply obtained by the various expeditions, which of late years have investigated the interior of the colony. This material, preserved in alcohol, has suggested to me an investigation of the above order. I hope soon to publish the results in extenso, but wish in this place to deal briefly with one point, namely the development of the ovule, the embryo-sac and the egg. As was mentioned above, the material was fixed in alcohol, but the fixation nevertheless proved to be good enough to allow of many cytological details being made out with a sufficient degree of certainty in stained preparations. In this preliminary communication I do not propose to discuss the method of treatment of the preparations, but merely record, that Messrs. A. H. Blaauw and J. K u y p e r have assisted me. A complete developmental series could only be obtained in the case of a few species, namely of Oenone Imthurni Goebel and Mourera fluviatilis Aubl. Of eight other species only a few stages of the development were examined, and of Tristicha hypnoides Spr. I only had the ripe seeds.