Ways and Habits of Caterpillars. 203 
the space between the web and the surface of the leaf, and feeds on the green 
matter of the leaf without gnawing quite through. Near the lowe1 end of its 
home, however, it gnaws in the leaf a circular hole by means of which it 
disposes of its droppings. 
The cases constructed by Psychids and certain Tineids are for purposes of 
protection and concealment. The same purposes, however, are attained in 
a somewhat different way by the caterpillars of certain Geometers, for example, 
that of the pretty green Aplodes frondaria, and that of the rusty mottled brown 
Eupithecix. The caterpillars of both are flower feeders, that of the former 
feeding on the flowers of the weeds Clibadium, Hyptis, Christmes bush, and 
blacksage, and that of the latter on flowers of Clibadium. They both contrive 
to escape detection by attaching to their back bits of the flowers they feed 
on, and, the caterpillars being somewhat rough, the rugosities afford excellent 
points for the attachment of foreign material. tis not a little difficult te spot 
the caterpillars beneath their mantle of fresh and decaying vegetable matter. 
One of the most interesting caterpillar cases is that of the moth Perophora 
lucesta, of the family Perophoride. The caterpillar feeds on the leaves of the 
Laguncularia, a tree common along the sea-shore and the river banks where the 
water is salt. Its case consists of a leaf folded over edge to edge, so as to form 
a cylindrical tube open at both ends. The leaf is often severed from the plant 
but is always attached to the stem and surrounding leaves by a few stout 
threads, which are increased and strengthened when pupating time arrives. 
It is lined within with silk, and is placed so as to be more or less hidden by 
the neighbouring leaves. The hind part of the caterpillar is hard, rough, and 
flattened, forming indeed an oval plate, which exactly fits the opening at the 
back of the leaf-case. To see the caterpillar thus close one of the openings 
of its case, reminds one of the manner in which the snail closes with its oper- 
culum the aperture of its shell. 
I may here menton that in the British Guiana Museum there is in the anthro- 
pological section an Indian necklace, one of the most curious and unique 
of its kind, composed as it is of 25 caterpillar protective cases strung together. 
The cases are undoubtedly made up of excrement, and it is probable they are 
those of the hammock-moth Perophora sanguinolenta, figured and described 
in the Cambridge Natural History. 
Various modes of locomotion obtain among caterpillars. Those in which 
feet are not much developed, such as Limacodids, advance with a pied 
steady slug-like crawl. To compensate for this lack, the under surfac 
of their body has developed great adhesive power, so that they are ants 
to move by merely undulating this part of their anatomy. The green Lima- 
codid caterpillar, already mentioned as being a common feeder on the castor- 
oil, is a typical example of this method of progression. Then there is the 
looping method that gives the name to a whole family of moths, viz., the 
Geometridz or Geometers, a term which, I need hardly say, means land- 
measures. The moths are so called because their caterpillars when walking 
appear to be measuring off the course along which they are travelling. The 
caterpillars have only one pair of abdominal feet, as compared with four pairs, 
