6 CLASS-BOOK OF BOTANY. 
‘der in which 
the receptacle. In this section we can see the order in whic 
each of the whorls is fastened. 
Fig. 1. Longitudinal section through flower of Buttercup 
(slightly magnified). 
The sepals are not very unlike simple foliage-leaves: they 
are oblong, somewhat concave or boat-shaped, and very hairy 
on the outside. In the buds they are seen to cover over the 
other parts, and we therefore consider thei function to be 
chiefly that of protecting the more delicate parts within. 
Notice also that in the buds the sepals le in a particular 
order: the edges of one of them overlap the one on each 
side of it; these, again, overlap the inner two, one of which 
overlaps the other by one margin; so that one is really the 
outermost of the five, and another the innermost. The ar- 
rangement of sepals and petals in the bud is called their 
cestivation,* and this is said to be imbricate when their 
edges overlap one another as in this case. All five sepals are 
separate from one another, and therefore we say their cohesion 
is aposepalous} (or polysepalous),} the term “ cohesion ”’ 
being applied to the union or relation of parts of the same 
whorl to each other. They are also attached to the recep- 
tacle below the other whorls, and so we say their adhesion 
is inferior, the term “‘ adhesion’’ being applied to the union 
of the organs of different whorls to each other. : 
The five petals are of a bright golden-yellow colour, 
and are attached by a very small base to the receptacle 
underneath the stamens and pistil. Being all free, their 
cohesion is apopetalous (or polypetalous), while their ad- 
hesion is said to be hypogynous,§ which really means the 
Bee ee ee BOY A Cy? Le ee he 2 oe oe 
_ "Lat. estivus, pertaining to summer, because flowers usually open 
im summer. The term prefloration is preferable to estivation, but the 
latter term is generally adopted. 
+ Gr. apo, from ; eee terms referring to the freedom of the se- 
; Gr. polus, many ; pals or petals from each other. 
§ Gr, hupo (hypo), under—the gynectun, or pistil. 
