122 BOTANICAL GAZETTE. [ May, 
dele points by em celled parenchyma 
T : 
ese three nechyma re ‘can be rec ognized on the surface of the 
tendril, as dark green bands extending through its length on the upper side and 
on the right and left ong these the greatest growth occurs in turn without 
d} 
regular — and ere the activity longest remains. The name vibrogen is 
be a tension in these tissues, ses resulting movements of the whole body. 
It has been demonstrated by Sachs and Darwin that a band of r rapidly grow ing 
tact depending upon the site distribution of the three vibrogen 
orsion is produced by the te am owth of the vibrogen bands not selloivea 
Irritation upon the surface of the tendril, pipapren 4 in the region of the 
collenchyma least broken by the parenc yma, i. é@., the lower purines causes 
cessation of growth and condensation of structure, je nee a bending ard the 
etoting surface. The same is true when coiling results from st nike 
support 
echanical irritation is applied at any part the impulse is con- 
eyed ol to cell through the ene of protoplasm which is best 
demonstrated in the collenchyma tiss 
fb movements eaearaiad 3 are also explained upon similar grounds, 
and the saisleaniion of these movements in tendrils alone is accounted for by 
the localization of the vibrogen bands, the disproportion between length nl 
diameter, the great flexibility of the organ and the greater — unequal 
tension when exerted longitudinally through a filamentous ee 
GRACE E. “Ghenee: 
Handbook of Plant Dissection. By J.C. Arthur, C. R. el gape M. Coulter. 
‘S Henr. a & Co., New York. 1886. 12°, pp. 2p 
f this volume has been to provide ep ss aie aor students 
3 deta sheets t of » series of representative types illustrating the dif- 
rent groups of the — kingdom from the lowest to the highest. As 
the tithe foe ban itis nota eral treatise to which the seas is to go for 
information, but a practical iedivck o be nsed in the laboratory while ex- 
° 
Pe 
y 
general. In an introductory chapter is a short t of th tus and 
: cate = - oe ort account of the apparatu 
re isa t need of a book like the present, for the pecs ° 
who soe to study botany by aan we may call the type-pla ay ehon ae lar, ree 
and increasing. In a work “ot this kind the temptation is to rabecterst too adueh 
