i 
Ixvill 
8th tergites of the abdomen. The gland when everted gave 
off two branches which stood erect to a height of nearly a 
mill metre, and, being of an orange colour, were quite easily 
seen with the naked eye. Eversible glands of a somewhat 
different kind, and very much smaller in size, were known 
to occur in the larvae of Lina populi and some other species 
of Chrysomelidae, where they formed a series along each 
side of the back, each gland being slightly everted from a 
minute opening at the top of a small conical tubercle; these 
glands each exuded a milk-white drop of liquid, which had an 
odour like that of bitter almonds, and was said to contain 
salicylic acid. The larvae of Phytodecta which he was exhibit- 
ing were given to him by Mr. Champion, who found them, 
together with the beetles, on their food-plant, a species of* 
Salix ; and he had not himself observed them under natural 
conditions. While investigating one of the larvae to see if 
it had glands like those of Lina, he touched it with a brush 
dipped in benzene, and almost immediately its glands were 
shot out, and thus brought to his notice. It was subsequently 
found that when a larva was squeezed between the fingers, 
or with a pair of forceps, its glands were also everted, but 
were not brought into view when the larva was poked about, 
or turned upside down, with a brush or even with the point 
of a needle. Xylol, applied with a brush, had the same 
effect as benzene; but ether, chloroform, alcohol, formalin, 
or vinegar, applied in the same way, failed to make the larva 
evert its glands; and yet in each case when benzene was 
afterwards applied, the glands were quickly everted. By 
placing a larva in a cell under a glass cover-slip and then 
touching it with a drop of benzene, it was seen that where 
the glands came in contact with the glass two small drops 
of a clear, transparent liquid were left behind, which slowly 
evaporated, a faint deposit remaining on the glass. The 
larvae of Phytodecta viminalis had been more than once 
described, but he had nowhere come across any reference to 
their eversible glands. These glands, like so many others 
of a similar character met with in insects, doubtless served 
as a protection from predaceous or parasitic enemies; but 
why benzene in particular should have such an effect in 
