184 THE OPEN BOOK OF NATURE 
are very small. When very young, the Slow Worm 
has a whitish appearance, but as it grows it becomes 
copper-coloured. It haunts manure-heaps, where it 
often brings forth its young, always in a living con- 
dition (viviparous), and it may also be found in 
thickets and heaps of rubbish. 
Before we leave this delightful resting-place, I 
want to tell you something about the meanings of 
some Latin words that are often used as specific 
names of plants. When you know those words and 
their meanings you will the more easily understand 
the habits of the plants to which they are attached, 
or the uses to which they have been put. 
The Watercress, as I told you, is named Nastur- 
trum officinale. The word officinale comes from the 
Latin officina = a workshop, or laboratory. The term 
is applied to plants that are, or have been, used medi- 
cinally. Watercress is supposed to have valuable 
medical properties ; hence its specific name officinale. 
The same term is applied to the Great Wild Valerian 
(Valeriana officinalis), of which I see some specimens 
about ready to flower by the side of the brook ; and 
to a number of other plants. Vulgaris is another 
commonly used word ; it means ‘“‘ common,” and is 
applied frequently to common species of genera ; 
take, for example, the Yellow Rocket (Barbarea 
vulgaris), which grows in the quarry, as well as by the 
side of the stream. The word perennis is from per = 
through ; annus=a year ; and it indicates that the 
plant to which it is attached is a perennial, living for 
several years. The Daisy is named Bellis perennis. 
Paluster is from palus=a swamp or marsh; the 
word occurs in Caltha palustris, the Marsh Marigold. 
