I90 TRUE TALES OF THE INSECTS. 



spines on the hind borders of the abdominal joints, 

 affording the pupa power of executing the same 

 manoeuvres as the chrysalid of Sesia, enabhng it to 

 move in the tunnel bored in the tree, and assisting it 

 out of its cocoon. 



The Castniidae are essentially proper to the warm 

 equatorial regions ; their geographical range, in fact, 

 extends only to Mexico and Central and Southern 

 America, while they find their greatest development in 

 Central America and Brazil. The few Castnioides, or 

 species of Megathymus, known, inhabit the southern 

 portion of North America, hailing from the Southern 

 States, from Florida, and from Arizona. The genus 

 Synemon appears to represent the Castniidce in the vast 

 continent of Australia. 



The } ^ncca Borer. 



Of these aberrant forms Megathymus yiuccc, the Yucca 

 Borer, is one of the most interesting. Although placed 

 with the Castniida?, none the less it has given great 

 trouble to systematists, having been bandied from the 

 butterflies to the moths ; and, it must be owned, some 

 still regard it as a genuine butterfly. This species is 

 common in the Gulf States of America over extended 

 regions, where its larva commits serious depredations, 

 of the nature that its popular name implies. 



