GALLS CAUSED BY BEETLES 
49 
south of England. Similar galls are caused on this plant 
by M. linariae. 
The swollen ovaries of the Figwort, Marsh Speedwell, 
and Brooklime, result from the presence of the larvae of 
M. beccabungae. Members of the allied family, Plantaginaceae, 
are also attacked by species of Mecinus. The larva of 
M. collciris causes an elongated swelling on the floral axis of 
the Seaside Plantain. The flower head of the Hoary 
Plantain is sometimes galled by Mecinus pyraster (see 
Plate VI., where Fig. i shows a normal flower spike con¬ 
trasted with an afflicted one, Fig. 2, containing the larva). 
The beetle (magnified; it is only 4 mm. long) is shown 
in Fig. 3. It is widely distributed. It also galls the floral 
axis of the Ribwort Plantain. 
Many cruciferous plants are attacked by beetles of the 
genus Ceuthonhynchus. The galls, for the most part, are 
rounded or fusiform swellings at the base of the stem and 
on the roots. The most familiar of all coleopterous galls 
are those caused by the presence of the larvae of Ceuthov- 
vhynchus sulcicollis Gyllenhal ( pleuvostigma Marsh) on the roots 
of Turnips, Swedes, and various kinds of Cabbage. They 
are often coalescent; a single gall is a smooth rounded 
protuberance, usually about the size of a large pea, situated 
on the upper part of the root, just below the surface of the 
ground. The beetle is minute, about 3 mm. long. The 
elbowed antennae are situated on the long, stout proboscis, 
a characteristic of the weevil family ( Curculionidae ) to 
which these beetles belong. The eggs are generally de¬ 
posited in holes made by the proboscis, usually one in each 
hole. The larvae are yellowish-white, thick, legless, and 
armed with dark brown jaws. They are at first difficult to 
observe within the gall, but later they hollow out its centre 
and are easily found. When full fed, the larva leaves the 
gall, and makes a hard case of earth, etc., in which it 
pupates. The imago emerges about six weeks or two 
months later. This gall may be found throughout the 
year, sometimes with living tenants even in severe weather. 
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