184 NOTICES OF BOOKS. 
Le Calice des Composées. Essai sur lunité du développement 
histologique dans le Régne Végétal. Par Samsoz Lunp, Cand. 
Phil. (From the “ Botanisk Tidsskrift,” 1872, pp. 140.) 
Tue object of this essay is to establish the foliaceous nature of the 
pappus of Composite. e author has specially examined the 
development of the pappus of Cirsium arvense, and from the stud 
of it concludes that the pappus consists of leaves, each leaf containing 
a true fibro-vascular bundle, generally consisting of cambiform cells, 
but under certain circumstances developing spiral vessels. Unfor- 
tunately we do not think that the pappus can be thus easily disposed 
of. What are we to make of the two scales in Helianthus, or the 
numerous whorled scales of Centaurea? Judging from the structure 
of the flower of the Composite with five petals and five stamens, we 
should naturally expect five parts of the calyx opposite the stamens 
and alternating with the petals. Now it is only in a few very 
cases that we find the pappus developing from these five spots 
Th i 
4 
Be 
= 
~ 
= 
oe 
Q 
i] 
ot 
oO 
a 
a 
o 
“= 
— 
2 
QO 
fa>) 
—e 
j=) 
mh 
is =} 
pale 
= 
o 
mt 
ou 
|= a4 
oO 
rs 
© 
<) 
m 
—_ 
ot 
co 
n 
B 
° 
cr 
= 
bs) 
S 
Oo 
4 
consists first appear. As already mentioned, the parts of the pappus 
rarely develope at the five places where we would a priort expect 
calyx leaves to form. In Bidens with a pappus consisting of from 
2—4 bristles, or in Helianthus with 2 scales, the parts are developed 
ly. 
bristles, or hairs of the pappus are undoubted trichome structures. 
Lund seems to have studied an exceptional form, and thus been led 
A part of the essay is devoted to the consideration of Hanstein’s 
dermatogen, periblem, and plerom. Lund does not agree wi e 
. Those who wish for fuller information on the development of the 
flowers of Composite should consult the papers of Buchenau in the 
Botanische Zeitung,” 1872, p. 305, et seq. 
W.R. McNas. 
