528 T. Holm — Mollugo verticillata L. 



particular habit of the species with the unequal development 

 of the foliage and with the plagiotropic shoots, is noticeable at a 

 very early stage of the plant, beside that it occurs in small, 

 depauperate specimens where only two or three branches may 

 be developed ; in other words, the species shows a typical exam- 

 ple of what Goebel has designated as " habituelle Anisophyllie" 

 (1. c. p. 93). This peculiar deviation in the development of 

 foliage is not, however, characteristic of all herbs with prostrate 

 stems ; it does not, for instance, occur in such plants as Euphor- 

 bia maculata, nor in Stellaria media, Callitriche Austinii 

 and many others. It seems to be restricted to certain genera 

 of widely different plants, as stated above, and we might men- 

 tion at this place, that it is exceedingly well represented by 

 Abronia fragrans Nutt. In this plant the stems are prostrate 

 with the ieaves opposite, and the ramification is plainly sympo- 

 dial. Each shoot is terminated by an inflorescence, and the size 

 of the leaves in each pair is very unequal. Furthermore, it is 

 from the axil of the larger leaf that the long shoot becomes devel- 

 oped, which repeatedly terminates into an inflorescence and so 

 on. From the axil of the smaller leaf, on the other hand, only a 

 very short branch becomes developed, resulting in a very 

 unequal structure of the whole shoot, a succession of branches, 

 alternately to the right and left side of the main axis. Abro- 

 nia micrantha Torr. shows exactly the same structure, but it 

 is a smaller plant, thus the anisophylly and the sympodial 

 ramification is less plainly to be observed. In the near ally 

 Oxybaphus of much the same habit, the anisophylly is not to 

 be observed, not even in the species with the leaves broad, 

 although the ramification is the same, sympoidal. 



Another peculiarity possessed by Mollugo verticillata is the 

 alternation of long and short internodes, as shown in figure 4 ; 

 this type of structure is not very common, but represented by 

 several monocotyledonous and dicotyledonous genera, viz : 

 Munroa* Eriochloa, Cynodon, Androsace, Chimaphila,f 

 Erigeron (flagellaris G-r.), etc. In regard to the inflorescence, 

 this is in the Synoptical Flora (1. c), only described as 

 " flowers 2-5 from each node, slender-pedicelled, subtended by 

 foliaceous bracts " ; it is, however, cymose, and represents a 

 dichasium. The floral structure is rather peculiar, there being 

 five free sepals, no petals, mostly three stamens, alternating 

 with the three carpels ; the fruit is a membranaceous, loculi- 

 cidal capsule with several estrophiolate, rugose seeds. 



Now in respect to the internal structure of the vegetative 

 organs very little seems to be known about Mollugo' verticil- 

 lata judging from the treatment of the Ficoidece in Solereder's 



*Bot. Gazette, vol. xxxix, 1905, p. 123. 



f Merck's Eeport, vol. xviii, p. 143. New York, 1909. 



