30 THE DICTIONARY OF GARDENING, 
THRINCIA. Included under Leontodon. 
THRIPS (a Greek word for a moth). The name 
given to a group of small insects that often do much 
harm to cultivated plants, by gnawing the surface of 
flowers and tender twigs and leaves, thus causing 
withered and distorted spots to appear on them. The 
genus Thrips, along with certain closely-related genera, 
is ranked in a family known as the Thysanoptera (from 
thysanoeis, fringed, and piera, wings), or as Physopoda 
(from physa, a bladder, and poda, feet). Both names 
allude to characteristic features in the structure of the 
fully-developed insects. Thrips are very common in 
flowers, crawling about the interior of the corolla tube, 
and over the stamens, or living upon or in the fruits, 
_ or on the lower surface of the leaves. They feed upon 
~ the more delicate parts of the plants, causing them to 
_ become withered and blighted. The mature insects are 
very small, and are black or dark-coloured. They are 
long and narrow, and are furnished with four straight, 
narrow wings, which are fringed with long hairs, and 
_ have few, if any, veins (see Fig. 24). They have three 
pairs of legs, on which the last joints end in a bladder- 
like swelling without claws. The mouth is provided with 
panta sation ie oiea delicate tissues of plants, and 
Sor eneking iett HOM The earlier siagon. in the de- 
Thrips—continued. 
velopment of the species of Thrips are much like the 
mature insects, save in colour (which is usually dull 
yellow), and in the wings being entirely absent from 
the larvæ, and represented only by short wing-cases in 
the pupæ. The structure just described renders the 
order intermediate between Orthoptera (to which Grass- 
FIG. 23. THRINAX RADIATA (see page 29). 
hoppers, Locusts, &c., belong) and Hemiptera. See 
Insects 
hl 
SLL 
Fie. 24. THRIPS (magnified). 
Many species have been described, so much alike as 
to render it very. hard to distinguish them from each 
