T. Holm — JErigenia hulhosa. 63 



Akt. Y. — Erigenia oulbosa Nutt. A morphological and 

 anatomical study ; by Theo. Holm. (With six ligures in 

 the text.) 



While not especially interesting in morphological respects, 

 the UmheMiferce, nevertheless, possess types which have 

 attracted some attention, though more by the structure of 

 their flowers and inflorescence than by their vegetative organs. 

 The seedling-stage, with the first development of rhizome and 

 roots, has been studied in only a relatively small number of 

 species by Bernhardi, Hegelmaier, Irmisch, Klebs, Lubbock, 

 Winkler and others, and in regard to the mature plants, there 

 are many species, which are so little known that it is alto- 

 gether conjectural whether their underground organs represent 

 roots or rhizomes ; even in the "Revision of North American 

 TImbelliferw" * the authors have made no attempt to draw the 

 distinction between roots and rhizomes, but state simply : " We 

 use roots here in the ordinary systematic way. Morphologically 

 these tuberous roots are mostly subterranean stems." Con- 

 sidered from an anatomical view-point the order seems to be 

 known much better, and we find in the literature several 

 papers with accounts of the anatomy and some very compre- 

 hensive studies of the oil ducts, which are particularly well 

 developed in this order ( Umbelliferce). 



Thus it would appear as if there were a number of vacant 

 spaces to be filled in the life-history of the order, and it is, 

 therefore, our intention to present some brief notes as a con- 

 tribution to the knowledge of one of its members, the 

 " Harbinger of spring " : Erigenia hulhosa. 



It is a plant, which has, for a long time, attracted our atten- 

 tion on account of its globular underground part, by JSTuttall 

 correctly defined as a tuberous root. Having made a special 

 study of similar plants with tuberous, underground parts, we 

 have often desired to ascertain how far Erigenia possesses a 

 true tuber or a tuberous root. It is, however, not always satis- 

 factory to study plants of this nature only from adult speci- 

 mens, and the publication of observations of this plant has 

 been postponed for a considerable period until we succeeded in 

 obtaining material in the seedling stage. The seedlings are, as 

 a matter of fact, not easily found, and it was not until last 

 spring that we detected some young plants, which proved to 

 be the seedlings of Erigenia. Several years ago, in the early 

 spring, we collected quite a number of seedling plants with 

 only one cotyledon, just as we expected to find in Erigenia^ 



*For references consult the Bibliography appended to this article. 



