genous only when the gynaecium and its envelopes occupy the whole (or 

 very nearly the whole) of a very short branch, such an inflorescence 

 having heretofore been mostly accounted lateral ; but when it occupies the 

 apex only of the main stem, or of a long branch, I have considered it 

 acrogenous. Several CephalozicB have both the stem and its more or less 

 elongated branches floriferous at the apex. The same thing occurs in 

 certain subpinnate PlagiocMla, where the inflorescence is mostly 

 terminal on the branches — more rarely on the main axis — and yet is in 

 every case to be accounted truly acrogenous. Where the stem is 

 dichotomous, and the main axis terminates at the first forking — or (if 

 you will) is being repeatedly doubled — the inflorescence may still be 

 acrogenous, as is seen in Blepharostoma, the Plagiochilce § Cristata, &c. 

 &c.; but in the similarly-branched Bazzania the $ flowers, consisting 

 each of a short postical branch, are truly cladogenous. — When I speak 

 oi flower-leaves, or anthophyls, I mean the three (more rarely only two) 

 innermost involucral leaves, whose marginal union constitutes the 

 tubular perianth, or colesule. They are thus exactly analogous to the 

 petals of (for instance) the primrose, whose union constitutes the 

 gamopetalous corolla. \Tlh.e folia floralia of some authors are the leaves 

 exterior to the whorl next the perianth, this innermost whorl alone 

 constituting for them the true involucre. I call them, what they really 

 are, outer bracts.] 



It only remains for me to gratefully acknowledge the aid I have re- 

 ceived, in the way of specimens of many of the plants described, espe- 

 cially from Messrs. Caekington, Hooker, Hxjsnot, Limpeicht, Lindbeeg, 

 Peaeson, Slatee, and Stablee. 



ElCHAED SpEUCE. 



Coneysthorpe, near Malton, 

 Sept. 27th, 1882. 



