Feb., 1904.] Nymphaeaceae and Helohiae. 83 



SOME MORPHOLOGICAL PECULIARITIES OF THE 

 NYMPHAEACEAE AND HELOBIAE.^^ 



John H. Schaffner. 



Having spent some time in studies upon various species belong- 

 ing to the Helobiae, the writer has naturally taken considerable 

 interest in the recent investigations by Lyon, Cook and others 

 on the enibryogeny of the Nymphaeaceae. On account of cer- 

 tain peculiarities in the anatomical structure of these plants, 

 the writer following many others had reservedl}' placed the 

 Nymphaeaceae near the Helobiae ; but, because of the supposed 

 characteristic Dicotyl embr3'0 and certain Dicotjd features which 

 were read into the flowers, it was thought improper to take them 

 away from their "authoritative" position. However, since the 

 way has been considerably cleared b}- L3'on and Cook, at least so 

 far as the embryo is concerned, for judging certain other charac- 

 ters of the group on their merits, a considerable study has been 

 carried on for the last three years upon various species of the 

 group. 



It might perhaps be proper to state here that the writer had 

 the pleasure of examining most of Cook's preparations on which 

 his more important conclusions were based ; even going so far as 

 to reconstruct the earl}- stages of the embrj'o which showed that 

 in Nymphaea advena the development of the so-called cotyledon 

 is essentially the same as what Lyon had reported for Nelumbo. 

 It is unfortunate that Coulter and Chamberlain in their "Mor- 

 phology of Angiosperms" overlooked the reference to Cook's 

 embryo of Nymphaea advena. For the fact that the embryo of 

 Nymphaea has such a close resemblance to Nelumbo must have a 

 very important bearing on the subject. 



As is well known, the vascular bundles of the Nymphaeaceae 

 are essentially Monocotyl in type, showing the characteristic 

 closed bundle. So striking is this in the bundles of the flower 

 stem of Nelumbo that one might almost palm off a section for a 

 corn bundle. The disposition of the xylem and vessels, the 

 phloem, and the cap of sclerenchyma, taken together with the 

 scattered arrangement and the absence of secondary cambium 

 certainl}^ represent a structure characteristic of Monocotyls (Fig. 

 I ). The vascular bundles of Podophjdlum and certain species of 

 Piperaceae which the writer examined are considerably different 

 and show the open type of bundle characteristic of Dicotyls. 

 These plants have therefore no important bearing on the relation- 

 ship of the Nymphaeaceae so far as the anatomy of the stem is 

 concerned. 



The many superficial characters must also be taken into con- 

 sideration. The similarity of habitat, the rhizome habit, the 



*Contribtitions from the Botanical Laboratory of Ohio State University, XVI. 



