154 On the Caterpillar which 



Naturalists, so far as they have explained themselves, 

 at least such as I have been able to lay my hand on, 

 describe the Caterpillar as coming from the egg of the 

 mother, a reptile, naked and exposed, without shelter, 

 and without covering (from these are excepted, such 

 as leave and return to their shelter) ; that it passes 

 through life defenceless, a prey to its enemies, until it 

 shall arrive at a certain state of maturity, and enter its 

 aurelia state. The Poplar- Caterpillar is, in early life, in 

 the first days of its reptile existence, sheltered, defended 

 by a case or husk, and remains in this habitation, ap- 

 pended to the lower surfaces of leaves, until it shall ac- 

 quire about one-fourth of its growth, when it affranchises 

 itself, and roams abroad, seeking its subsistence. In this 

 state it continues until its majority as a reptile, when it 

 enters its chrysalis state. 



Reaumur describes the Caterpillar as having six spots 

 on the first ring, which serves for its head, and supposes 

 it probable that they are eyes. The poplar reptile has 

 in the place of six spots (six petits grains noirs), two 

 lines running from its mouth to the vertex of its head. 

 This reptile is from two and a half inches to three, mea- 

 suring from its head to the extremity of its tail or body. 

 It is of a chocolate colour ; some are rather browner ; is 

 composed of two unequal cones meeting at the bases, 

 and their junction is marked by a zone or band dissimi- 

 lar in colour from the rest of the body. These cones 

 are in themselves made up of separate membranous 

 rings, united not so much by suture, as intussusceptio. 

 The mouth of this reptile is vertical, being parallel with 

 a line raised to a perpendicular from the horizon. Its 



