— 19 — 



For full accounts of the receptacles reference may be made to the published 

 descriptions and especially to the work of Schiffner. It is sufficient to state 

 here that the male receptacle is stalked as in Preissia and Marchantia, that 

 the disc of the female receptacle is bluntly lobed, that the groups of archegonia 

 (each enclosed by a membranous involucre) lie beneath the lobes, and that each 

 sporcphyte is enclosed within a pseudoperianth. Here again Bucegia resembles 

 Preissia closely and also agrees with such species of Marchantia as the Asiatic 

 M. geminata R. Bl. & N. and its allies. The photosynthetic tissue of both recep- 

 tacles is, however, essentially the same as in the vegetative thallus and therefore 

 differs markedly from the branched rows of cells found in both Preissia and 

 Marchantia. 



4. FossoMBRONiA LAMELLATA Steph. Hedwigia 33: 9. 1894. F. tuberifera 

 Goebel, Organographie der Pflanzen 292. /. igo, igi. 1898. [Figs. 1-4.] 



Collected in December, 1915, May, 1916, and January, 1917, at Sanford, 

 Florida, by S. Rapp (No. 80). New to North America. The species is char- 

 acterized by the possession of numerous tubers, some of which are highly differ- 

 entiated while others are more rudimentary. The material collected in 1917 

 shows mature capsules. 



Apparently Ruge, in 1893, was the first to describe tubers in the genus 

 Fossomhronia} His material, which he does not attempt to name, was collected 

 by Goebel at Tovar, Venezuela. He states that the stem of a tuberiferous plant 

 turns dcwnward instead of upward and becomes swollen at the apex, the enlarged 

 portion, or tuber, being filled with stored food, some of which is in the form of 

 starch. One of his figures shows the change in the direction of growth, but no 

 sign of a tuber, although the leaves exhibit a characteristic reduction in size. 



The following year Stephani described F. lamellata from Argentine specimens 

 in the Otto Kuntze herbarium, collected by R. Hauthal at Buenos Aires, no 

 other material being cited. He makes no mention of tubers but gives an account 

 of the vegetative structure and capsules and doubtfully assigns a monoicous 

 inflorescence to the species. 



A few years afterwards, in 1898, Goebel published his F. tuberifera, giving 

 a general account of the plant and two interesting figures in which the character- 

 istic tubers are brought out. One figure (/. iQo) shows a short plant with arche- 

 gonia, which has grown out from the tip of an old tuber; the stem, without 

 branching, turns abruptly downward and swells distinctly at the apex into a 

 new spherical tuber. The other figure (/. iQi) shows a plant which bears a 

 sporophyte, while the apex of the stem is beginning to show the characteristic 

 modification into a tuber. Goebel's material of F. tuberifera came irom Peldegue. 

 Chile, and he doubtfully assigned to the same species the Fossombronia from 

 Venezuela which Ruge had already discussed. 



In 1900 Stephani- published a new description of his F. lamellata and cited 

 F. tuberifera definitely as a synonym. In addition to Hauthal's specimens he 



> Flora 77: 30S. 306. pi. 4. /• 6: text f. 14. 1893. 

 ■ Mem. Herb. Boissier 16: 30. 1900. 



