208 Trans. Acad. Set. of St. Louis. 



produced from a single seed and while the eight seedlings 

 which first attracted my attention were normal, dissection of 

 nine seeds from a single fruit collected in 1893( ?) shows more 

 than one embryo in three cases, while the others were with but 

 one. Lynch in his paper figures the seedling of a Pachira 

 sp. (PL VIII, fig. 7) showing the adherence of two others of 

 arrested growth, resulting from the production of several 

 embryos in one seed. Unfortunately the size of this seedling 

 is not indicated on the plate, but in general appearance it 

 agrees quite well with young stages of P. campestris and it 

 perhaps belongs to this species. 



Some very striking differences are noticed between the ger- 

 mination of P. catnjjestris and P. aquatica. In both there is one 

 large and one small cotyledon, the smaller being in both a little 

 above the other. In P. aquatica, according to Lynch, the 

 small cotyledon soon falls away while the larger persists for a 

 long time, but in two or three cases in P. cavnpestris the smaller 

 cotyledon persisted the longer. The most striking point of 

 difference is in the relative development of hypocotyl and 

 epicotyl in the two forms. In P. aquatica, according to 

 the plate given by Lynch, the hypocotyl is developed hardly 

 at all, the cotyledons remaining almost if not quite on the 

 ground and but a short distance above the lateral rootlets, 

 while the epicotyl undergoes a very extensive development 

 extendinsf for a considerable distance before foliage leaves are 

 borne, while these are separated by fairly long internodes, 

 the whole presenting a very slender, graceful appearance. In 

 P. cainpestris the case is quite different. The cotyledons are 

 at once carried up for some distance on a strongly developed 

 hypocotyl, and it is some time before the plumule undergoes 

 much development. When it does, it does not reach a length 

 comparable with that figured for P. aquatica, while the large 

 foliage leaves are separated by but comparatively short inter- 

 nodes, the whole plant giving the impression of a much 

 stouter, more broadly spreading form than P. aquatica. 

 What may be the significance of these differences would be 

 hard to suggest, but it would be of great interest to know 

 the ecological conditions under which the two species are to. 



