The tail, notwithstanding so much practice, does not
seem to be able to find its way to the mouth; at least the neck
was always touched first, and apparently as a guide.

When we were at Bahia, an elater or beetle (Pyrophorus
luminosus, Illig.) seemed the most common luminous insect.
The light in this case was also rendered more brilliant by
irritation. I amused myself one day by observing the springing
powers of this insect, which have not, as it appears to
me, been properly described. [5] The elater, when placed on
its back and preparing to spring, moved its head and thorax
backwards, so that the pectoral spine was drawn out, and
rested on the edge of its sheath. The same backward movement
being continued, the spine, by the full action of the
muscles, was bent like a spring; and the insect at this moment
rested on the extremity of its head and wing-cases.
The effort being suddenly relaxed, the head and thorax flew
up, and in consequence, the base of the wing-cases struck
the supporting surface with such force, that the insect by
the reaction was jerked upwards to the height of one or
two inches. The projecting points of the thorax, and the
sheath of the spine, served to steady the whole body during
the spring. In the descriptions which I have read, sufficient
stress does not appear to have been laid on the elasticity of
the spine: so sudden a spring could not be the result of simple
muscular contraction, without the aid of some mechanical
contrivance.

On several occasions I enjoyed some short but most pleasant
excursions in the neighbouring country. One day I went