65 



HOMOLOGY OF THE FLORAL ENVELOPES IN 

 GRAMINEM AND CYPERACE.E. 



By F. Townsend, M.A., F.L.S. 



It is now more than ten years since I called attention, in the 

 pages of this journal,* to " some points relating to the morphology 

 of Carex and other Monocotyledons." In my paper on this subject 

 I then stated that I hoped, on a future occasion, to shew " that 

 there is a great similarity in the construction of grasses and 

 sedges, and that the correlative position of their parts leads to the 

 conclusion that the two-nerved or keeled inner pale of grasses is a 

 single floral bract. I propose now, in a measure, to fulfil that 

 promise, in the first place by recording my notes on several 

 species belonging to the orders Graminece and Ct/peracea;, and 

 secondly, by stating the conclusions which may be drawn from the 

 facts brought forward, and my present paper may be considered as 

 supplementary to my former one. I say in a measure, because I 

 am aware that the subject might be better and more fully handled, 

 but as time and opportunity might fail me, it seems better that my 

 promise should be even imperfectly rather than not at all fulfilled. 



Notes 011 several species belonf/mr/ to the order Ci/peraced, examined more 

 particularly with the view of ascertaining the homology of the parts 

 of the inflorescence. 



Cabices : Heterostachya;. 

 (In all the following species the ochrea is short.) 



Carex riparia. — The ochrea in this species is short, cloven to 

 the base and dark-coloured (Tab. A., fig. 2). The ochrea of the 

 upper female spikes is swollen at the sides (Tab. A, figs. 2, and la), 

 and approaches nearer to the form of the utriculus, shewing the 

 passage of the ochrea into the utriculus. 



At the base of every male spike will be found, universally 

 present, a fertile flower with single open glume or utriculus situate 

 next the main axis, alternate with and opposite to the primary 

 bract from which the male spike springs. 



There is an analogy between the bracts subtending the female 

 and barren flowers and the utriculus, both being of the nature of a 

 bract. This analogy may be well traced in the bracts of this 

 species, see Tab. A, figs. 3, 4, 5, 6. 



I have met with several instances in which the bract subtending 

 the utriculus has become bifid and three-nerved, also trifid and 

 three-nerved (see Fig. 7, b and c). These bracts had one utriculus 

 within their axil. It is easy to conceive this trifid bract as pointing 

 to the true nature of the three stamens, viz., a single trifid organ, 

 each division bearing one anther. 



It was in the examination of this species that I first discovered 

 the true nature of the ochrea and utriculus, and saw that the 



* Journ. Bot. 1873, p. 10-2. 

 JouKNAii OF Botany. — Vol. 23. [March, 1885.] f 



