THEOBY OE THE GBOWTH OF CUTTINGS. 419 



The same kind of argument might, I believe, be applied when 

 any other function of a branch is interrupted through injury. 



If this conclusion as to the growth of the most apical bud on 

 mutilated branches of the Bramble be correct, it may, I believe, be 

 directly applied to explain the growth of bramble-cuttings. 



In a bramble-cutting the only growth which takes place, whether 

 of roots or branches, tends to occur at the apical end. Such a 

 cutting resembles, in fact, one of the above-mentioned mutilated 

 branches, except in that it has been separated at its base from the 

 parent plant. And the morphological force which resides in the 

 cutting is the same thing as the regenerative impulse which makes 

 the more apical buds take up and continue the function of a 

 branch whose apical part has been injured. 



A Kevision of the Genus Vibrissea. By William Philips, F.L.S. 



[Abstract. Read January 20, 1881.] 

 In this communication the author in his introduction reviews the 

 genus as established by the late E. Fries of Sweden ; and he refers 

 to the various species added by subsequent writers. He notices 

 the curious characteristic phenomenon of their projecting their 

 long slender sporidia with great force, and their giving a velvety 

 appearance to the hymenium when removed from the water in 

 which they grow. Crouan's Vibrissea Guernisaci differs in form 

 from the genus as originally defined by the absence of a stipes ; 

 and hence some authorities have inclined generically to separate 

 it ; but Mr. Phillips finds it projects its sporidia, and for this 

 and other reasons retains it and three other species in a sessile 

 division of the genus. He selects V. truncorum as a typical form, 

 and describes in detail its minute structure and other peculiarities. 

 Thereafter he amends the definition of the genus as follows :— 



Vibrissea, Fries, awiend.-Aquatic fungi (except V.rimarum) bearing 

 the exposed hymenium on a plane or cup-shaped membranous receptacle, 

 stipitate or sessile, fleshy in texture, firm, ejecting from the asci slender 

 elongated sporidia, which often remain attached by their extremities to the. 

 surface of the hymenium, giving it a velvety appearance. Hab. On decayed 

 wood, submerged in water. 



Descriptions of eight stipitate and four sessile species follow ; 

 and V. Persooni, Corda, and V.pubescens, Kabh., are rejected. The 

 paper in full, with plates, will appear in the Society's ' Transac- 

 tions.' 



LINN. JOTJBN. — BOTANY, VOL. XVIII. 2 I 



