NOTES. 53 
The full-fed larva is of a uniform grass-green colour. Vertex of 
head with a very minute conicle tubercle on each side; terminal 
segment with two longer tapering pointed processes directed 
backwards. Under a lens the derm is seen to be roughened with 
numerous minute white or colourless specules, some of which give 
rise to fine short hairs—those on the dorsum black, the others 
colourless. The points of the posterior processes are tinged with 
BE, Spiracles minute, black. 
- During development the caterpillars fed only at night. They 
retired towards the roots of the plant at daylight. 
January 8.—Two of the larve have pupated. The chrysalis is 
of robust form ; the dorsum of the thorax strongly convex ; four 
prominent transverse ridges across dorsum of abdomen. The two 
pupe are dissimilar in colour: One is pale grayish-brown, faintly 
streaked and mottled with darker brown and purplish markings ; 
the abdominal ridges pale ochreous, bordered in front with dark 
brown ; a pale ochreous lateral stripe. The second is of a grass- 
green colour, mottled with blackish streaks and spots. 
January 19.—The butterflies have emerged, the total develop- 
mental period having occupied fifty-four days, of which seven were 
passed in the egg, thirty-six in the larval, and eleven in the pupal 
stages. 
(6) Curious minatory action of a harmless Snake.—A young 
example of Dipsas ceylonensis, in my vivarium, exhibits a curious 
action when handled or disturbed. The terminal 2 inches of its tail 
are vibrated rapidly in short spasms. This is probably a minatory 
action, and is suggestive of the vibration of the tail of the rattle 
snake of the Western Hemisphere. The genus Dipsas (or Dipsado- 
morphus) contains several species of tree snakes, all of which have 
a distinctly viperine appearance both in form and colouration, 
though they are really quite harmless. The fact that they have 
grooved fangs (though destitute of poison gland) suggests that they 
may have descended from a venomous ancestor ; and the habit of 
vibrating the tail noticed above rather strengthens this idea. 
(c) A living chain of Ants.—(January 8.)—Mr. T. Petch has just 
drawn my attention to a living chain of ‘‘red ants’? (Acophylla 
smaragdina) spanning a gap 3 inches in extent between the leaf 
of a shrub occupied by the insects and a plant immediately below. 
When first observed the chain was some 3 insects thick and bifur- 
cated above, being supported at the upper extremity by two ants 
to each branch of the chain. These supports held on to the leaf by 
their feet, and each firmly held in its jaws the foot of one of the 
next links in the chain. These, in their turn, were gripped by 
the members below, and so on, until the base of the chain or 
column was held taut by the lowest members on the leaf below. 
This living chain was being utilized as a bridge, or rather ladder, 
