^16 T. Holm — Studies upon the Cyperaceoe. 



Perianthium. — (B.. Brown, 1810; Mirbel and Kunth, 1815; 

 Lestiboudois, 1819. Presl, 1820.) 



Perigynium. — (!Nees ab Esenbeck, 1835 ; Torrey, 1836 ; Dyer 

 and McNab, 1875; Bailey, 1889.) 



Phycostemon. — (Turpin, 1819.) 



Soucoupe. — (Adanson, 1V63.) 



Spathellules.~{^. Fr. Gray, 1821.) 



Tunica. — (Ventenat, 1807.) 



Urceolus. — (DeCandolle, 1813 and 1819; Gaudin, 1811.) 



Utriculus. — (Scheuchzer, 1719; Kuntb, 1837; Roeper, 1844; 

 Richard, 1846; Steudel, 1855; Townsend, 1873; Eicbler, 1875; 

 Caruel, 1878; Lindberg, 1885.) 



Vesicula. — (Tournefort, 1700.) 



By comparing these various terms and their definitions, 

 given in the respective works cited, the principal difference 

 seems to consist in whether this leaf should be considered as a 

 part of the flower or as a bract only, a prophyllon. It has 

 been considered as a pericarp, a nectary or disk, a perianth 

 and a perigynium, in contrast to its definition as one or two 

 bracts. 



The often bidentate apex might suggest its origin from 

 two primordia, if the history of its development has not 

 taught us different, besides the fact that it never, at least in 

 normal cases, supports more than one single flower. It forms 

 thus a most striking parallel with the palet, the palea superior, 

 of the GramineoB, so excellently discussed by Eoeper in his 

 Flora of Mecklenburg. We see, also, from the list of its 

 terms, that the name " utriculus " is of a very old date, and 

 that it has been adopted in several languages, and there is no 

 reason why it should not be preferred to the rather misleading 

 term "perigynium." It is, furthermore, an organ which is 

 absolutely identical with the ochrea described above, and it 

 constitutes together witii this the floral or antho-prophyllon of 

 the genus Car ex. 



It is now interesting to observe the transitions which exist 

 between the normal utriculus and the ochrea. That the struc- 

 ture of utriculus shows a vast number of forms is a fact, 

 which we know from the systematic treatises of our genus. 

 Some abnormal cases might, however, deserve mention. We 

 remember, for instance, that the rhacheola, which bears the 

 utriculus, often becomes elongated and bears flowers, especially 

 female ones. It is, in such cases, figured on our Plate II, figs. 

 2, 4, 5 and 6, that the utriculus becomes more or less modified 

 so as to present a development intermediate between that of a 

 typical utriculus and of an ochrea, besides that the inflores- 

 cence itself may simulate that of Elyna or of Schoenoxi- 

 phium. Such utriculi, of which the rhacheola has become 



