JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



country. It bears racemes of white flowers, reminding one of a Clethra. 

 It has recently flowered in the Trinity College Gardens, Dublin. — W. G. 



Cut Flowers, Hints about. By Alger Petts (Garden No. 1697, 

 P« 377; 28/5/1904). — It is a common experience that some flowers will 

 not continue fresh in water even for a day. Not only do they fade, but 

 the whole thing withers as if the stalk failed to reach the water. By 

 a knowledge of a few simple facts much disappointment and vexation 

 may be avoided. In the first place, all flowers should be put into water as 

 soon as possible after they are cut. If left out of water for some time 

 the cut ends become dry and shrivelled, with the result that some of 

 them have a greatly lessened power of absorption of water. In such 

 cases a half-inch or so should be cut off the ends of the stalks immediately 

 before they are put into water. This is a good plan to adopt with flowers 

 which have been travelling, in addition to which, in such cases, they 

 should be immersed in water up to their heads for an hour or so ; and if 

 the water is .tepid so much the better. — E. T. C. 



Cyaniding- Insect-infested Plants. By E. F. Hawes (Gard. 

 Mag. 2634, p. 274 ; 23/4/04).— The nature of this insecticide is described, 

 and detailed instructions are given as to its application to various kinds of 

 plants and the particular insect pest to be destroyed. — W. G. 



Cyanophyceae, Morphology and Physiology of the. By 



F. Brand (Beth. Bot. Gent. xv. pp. 31-64 ; 1 plate and bibliography).— 

 Gives a long and critical discussion of Resting spores, Limit cells 

 (heterocysts), Gonidia (conidia) and Mikrogonidia, Separation bodies, and 

 of the active movements of Hormogonia. 



The resting spores are produced without rejuvenation and under very 

 unfavourable conditions. Generally they are enlarged vegetative cells with 

 thicker cell-walls and stores of food material. The occurrence of these 

 resting spores in the different families is detailed. The heterocysts or 

 limit cells are, according to the author, connected (probably) by protoplasmic 

 threads with the neighbouring cells through the pores, and contain reserve 

 material. The author found them in Nostoc commtine, and states that 

 they give rise to gonidia. These gonidia (conidia) are formed by rejuvena- 

 tion and division, and directly pass into the vegetative condition without 

 a resting -period. The author describes his observations of them in 

 Phormidium uncinatum, Gom. The separation bodies may be either 

 dead cells or special intercellular excretions, and allow of the breaking-up 

 of a thread or the separation of a side branch. The substance excreted 

 seems not to be cellulose. The movements of Oscillatoria threads and of 

 those of other species are fully discussed. They appear to be caused by 

 light at least in part, but are, according to the author, in part autonomous. 

 The hormog( nia show at least three motions, viz. swimming in direction 

 of the longitudinal axis, twisting round the longitudinal axis, and, as 

 discovered by the author, turning of the longitudinal axis itself round its 

 middle point. In consequence of this last motion the free hormogonia 

 often follow a path which is a spherical triangle with the sides concave 

 outwards. — G. F. S.-E. 



