PROTECTIVE COLORATION AND DEFENSIVE STRUCTURES OF LARVAE. 101 



rested. One is puzzled to know exactly what advantage this com- 

 panionship would be to either larva, except that the spines of the 

 larger caterpillar might prove a sufficient protection to the smaller, as 

 Avell as to itself. 



On the other side of the question, viz., that in which the lepidop- 

 terous larva is the attacker, and not the attacked, we learn from Nice- 

 ville that the Indian Spalijis is very like the American Feniseca, since 

 the lame of both are carnivorous, associating with and feeding upon 

 the " mealy bug " of the planters, a species of Daetylopivi. 



Besides the protection offered, by the various means already de- 

 tailed, to larvas against their enemies, some remarkable instances of 

 protection against abnormal meteorological conditions are recorded. 

 One of these is recounted at length by Niceville (Butts, of Sumatra, 

 p. 538), and refers to the larva of a Hesperid, Erinota thrax, 

 which is covered with a white waxy powder, and lives in a shelter 

 made of a portion of one of the enormous leaves of Musa, which it 

 cuts into in order to obtain a suitable segment for its shelter. The 

 pupa is covered with the same white powder as is the larva, and is 

 quite hidden from view in its dining-room. This powder is of the 

 greatest service to the animal as, in consequence of the heavy showers 

 of rain in the tropics, much water often collects in the rolled-up leaf, 

 and the pupa, if not so protected, would soon be drowned and rot. As 

 it is, the powder keeps the pupa dry until the water has drained away 

 or dried up. The downy larva of the allied Gangara thyrsis is similarly 

 covered with a white waxy powder. There is no doubt that the wax 

 with which these larvje (that live in closed habitations) are covered, 

 is of the same value as that with which the pupa of Parnassim a polio 

 and others are coated, viz., to protect the larva (and pupa) from damp. 



We have previously referred to the passive defence offered by all 

 lepidopterous larvas, and the reason of this is not far to seek. The 

 peculiar form and character of these larvae lend themselves very readily 

 to injury. The larva cannot reply to its enemies in any way in which 

 the combat would resolve into a question of mere physical strength. A 

 small injury is almost as dangerous to it as a great one, and the loss 

 of blood resulting from a slight wound usually proves fatal. It is 

 probably owing to this that the various means of protection found in 

 lame are almost always of a passive kind. Such means of defence as 

 they have are almost entirely such as tend to prevent them from being 

 seen or touched, rarely such as are of any real service when they are 

 actually attacked. In some larvae there may be various modes, or 

 changes in the mode, of defence, but the object is always to leave the 

 larva untouched, a touch being practically fatal to it. The larva of 

 Xtauropwfatji, at rest, resembles a beech leaf. If disturbed, it adopts 

 a terrifying attitude, but if this be of no avail, the larva possesses no 

 other means of protection. The larvae of Geometrid moths resemble 

 pieces of stick ; when disturbed, many fall to the ground, but if 

 followed up here their means of defence are exhausted. The larva of 

 Cltoerocampa elpenor is protected by its similarity to its food-plant ; if 

 disturbed, it takes on a terrifying attitude, but again, if this fail, it 

 has no further means of protection. Warning colours, and unpleasant 

 or pungent secretions, are of no use against foes that once attack the 

 larva, for the slightest injury would p 

 found the prey inedible after capture. It 



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