22 BOTANICAL GAZETTE [JULY 
tooth of the capsule of Marsilia. The upper tooth, which in 
Marsilia consists simply of elongated epidermal cells, is entirely 
wanting in Pilularia. 
In conclusion, the sporocarp of Piludaria globulifera is essen- 
tially the equivalent of a Marsilia sporocarp in which the num- 
ber of sori has been reduced to two pairs, and will probably be 
found to correspond even more closely in development with 
those Marsilias, like -J/. polycarpa or M. A2gyptiaca, which also — 
have a small number of sori. Morphologically, then, we must 
in both cases consider the capsule as equivalent to a branch of 
the leaf in which the marginal cells have been devoted to the | 
formation of sporangia instead of a lamina. ; 
BALTIMORE, Mp. 
LIST OF WRITINGS REFERRED TO. 
BISCHOFF, G. W., ’28: Die kryptogamischen Gewachse. 1828. 
Bower, F. O., ’84: Comparative morphology of the leaf of the vascular 
cryptogams and gymnosperms. Phil. Trans. 175: —. 1884. 
RAUN, A., ’70: Ueber Marsilia und Pilularia. Monatsb. Berl. Akad. 
CAMPBELL, D. H., ’93: The development of the ene of Pilularia 
Americana. Bull. Torrey Bot. Club 20:—. 1893. 
ee ee ’95: The structure and development of the mosses and ferns. — 
GOEBEL, K., 82: Ueber die “Frucht” von Pi/ularia globulifera. Bot. | 
Zeit. 40: —. E882, 
HABERLANDT, G., '96: Physiologische Pflanzenanatomie. 1896. : 
HANSTEIN, J., 166 : Pilularie globulifer generatio cum Marsilia com-_ 
parata. 1866. ’ 
HOFMEISTER, W., ’62: On the germination, a eae. and fructifica- 
tion of the higher Cryptogamia, etc. Ray Soc I 
JOHNsoN, D. S., 98: On the leaf and s 
; rocarp of J ‘lia uadrifolia 
L. Ann. of Bot. 12: —, 189 per = ee " 
_ Juranyt, L,, ’80: Celle. die Gestaltung der F fuicht bei Pilularia atoll 
Jera. Bot. Centr. 1:—, 1880. 
a : itrge zur Kenntniss der Rhizocarpeen. 1846. 
EUNIER, A., ’87: La Pilulaire. Etude wenmaie tage du sporo- 
carpe chez la Pilularia globulj ifera. La Cellule 4:—. 7s 
POIRAULT, G., ’90: Recherches d’histogenie eeetale Mém. de l’Acade 
imp. de St. Péteiaboseg 37:—. 1890. ‘ 
