146 
CLASS PENTANDRIA 
LECTURE XXV. 
CLASS V. PENTANDRIA. 
Fig. 127. The class which we are about to exam- 
ine is said to comprehend more than one 
tenth part of all known species of plants. 
It differs from the class Syngenesia in hav- 
ing its Jive stamens separate, while the 'Syn- 
genesious plants have the same number of 
stamens imited by means of their anthers. 
"Plants with five stamens, including those 
which have anthers united, are said to con- 
stitute one fourth part of the vegetable king- 
dom. 
Order Monogynia. 
Asperifolice, or Boraginece. 
Here we find a group of plants called by 
Limiceus Asperifolice, a name derived from 
two Latin words, asper, rough, and folium^ 
leaf] signifying rough-leaved plants. These have monopetalous 
corollas, with five stamens and five naked seeds. The seeds are 
dicotyledons. Jussieu forms these into the order Boraginece, from a 
genus called Borago. "The change in the corolla of these plants, in 
general from a bright red to a vivid blue as the flower expands, ap- 
parently caused* by the sudden loss of some acid principle, is a very 
curious phenomenon."* 
The Cynoglossum is, perhaps, as common as any of the asperi- 
folice, or rough-leaved plants. Its common name is hound's-tongue, 
so called from its soft oval leaves. Although the Cynoglossum is 
classed with the rough-leaved plants, its pubescence gives to its 
leaves a softness appearing to the touch like velvet; it is about two 
feet high, the flowers are of a reddish purple, growing in panicles. f 
The Lungwort, (Pulmonaria,) which also belongs to this natural 
family, has two species in North America with smooth leaves. The 
Mouse-ear (Myosotis) is valued for its medicinal properties ; a spe- 
cies, the arvensis, or Forget-me-not, is an interesting little blue 
flower. The Gromwell {Lithospermum) is a rough plant with white 
flowers ; the bark of the plant contains so much silex or flinty mat- 
ter, as to injure the sickles of the reapers, when it grows in the field 
with the grain. The name, Lithospermum, is from the Greek, lithos, 
a stone, and sperma, a seed, in allusion to the hardness of the seeds. 
The Borago is an exotic very common in our gardens. The c.o- 
rolla is wheel-shaped, of a beautiful blue colour, having its throat 
closed with five small protuberances ; the stamens are attached to 
the tube of the corolla. You must take off the corolla carefully, 
and you will see the little scales which choked up the throat of the 
©orolla, and the manner in .which the five stamens adhere to it. 
Luridcc, or Solanece. 
We next meet with a family of plants, named by Linnaeus, Liiridw, 
from their pale or livid colour. Jussieu called them the Solanece, 
*' Smith. , 
t It is said that the leaves of this plant, if strewed about apartments infested with 
rats and mice, will expel these vermin. 
Class Pentandria— How different from the class Syngenesia— What are the char- 
acteristics of the family Asperifolise ?— Cynoglossimi---Lungwort--Myosotis— What 
other rough-leaved plants are mentioned in the first order of the fifth class ?— What is 
said of the Lurida3 or Solaneoe 1 . 
