Geological Society. 149 



the privet (Ligiistrum vulgare), the specimens of which were sent to 

 him by Mr, Greenwood Pirn. The arrested buds were numerous on 

 the stem and were not arranged in any special order, so that there 

 were probably both normal and adventitious buds, converted into 

 sphseroblasts, like those so well known on the stem of the beech. 

 Two peculiarities were noticeable : first, that the sides of the bud 

 had four rows of leaf-scars, aU internodes having been suppressed ; 

 and second, some of the arrested buds had produced opposite lateral 

 buds, right and left, at their base, thus forming a three-lobed struc- 

 ture. The transverse section, shown under the microscope, ex- 

 hibited a very remarkable contorted condition of the wood, with 

 only slight traces externally of medullaiy raj^s. Both pith and 

 cortex were well developed. The vessels were few and small, and 

 the whole appearance was very different from that of normal privet- 

 wood. 



Photographs of Diatoms exhibited. — Prof. Haddon showed some 

 fine photographs of Diatoms, from the War Museum, Washington, 

 made under a very large amplification (2000-3000 diam.) of great 

 beauty and clearness. 



Prof. E. Perceval Wright showed examples and drawings of a 

 new genus and species of Alcyonaria from the ' Challenger ' col- 

 lection. 



Variety of " Orit " from Bray Head exhibited. — Prof. V. Ball, 

 F.R.S., exhibited a section of a dense purple-coloured rock which is 

 found near the southern extremity of the section of Cambrian rocks 

 forming Bray Head. The mode of occurrence of this rock being for 

 the most part obscure, although at one point it is distinctly stratified, 

 this, together with its density and hardness, made it desirable to 

 examine its microscopical characters. It proves to be a distinctly 

 clastic rock, consisting mainly of small fragments of quartz in a 

 ferruginous matrix. It may be regarded as a somewhat exceptional 

 variety of the class of rocks of this age to which the term " grit " 

 used to be applied by Prof. Jukes. 



GEOLOGICAL SOCIETY. 



April 15, 1885.— Prof. T. G. Bonuey, D.Sc, LL.D., F.E.S., 



President, in the Chair. 



The following communication was read : — 



" Notes on the Polyzoa and Poraminifera of the Cambridge 

 Greensand." By G. B. Yine, Esq. Communicated by Thomas 

 Jesson, Esq., E.G.S. 



After commenting on the want of published information con- 

 ctrning the Polyzoa of the Cambridge Greensand, as shown by the 



