BAG- WORMS ON ORANGE. 145 



basket is diflfereiitly construcled to suit its siiirouucliugs; on oak it is 

 usually formed of bits of rounded twigs, i)Utced crosswise after the fash 

 ion of a log cabin ; on trees with dense foliage like the Orange it is oftener 

 fashioned with leaf material. In all eases it is thickly lined and tirnily 

 bound together with strong, grayish-white silk, and is too tough to be 

 torn asunder with the lingers. Before the larva becomes a pnpa the 

 bag is suspended by a band of silk to a (wig or branch. 



The winged male esca])es from the sack leaving the pupa shell pro- 

 truding. It is a rather thick-bodied moth of dark brown color. The 

 abdomen is very long, slender, and tapering to the point, which is 

 armed with a pair of shell like claspers, and these conceal the point of 

 the intromittent male organ. These parts are very elastic and extensile, 

 and enable the male to reach deeply into the sack of the female, in the 

 act of coupling. The fore-wings of the male are rather long and nar 

 row; they arc slightly paler than the body, and are marked with a 

 short oblique line, devoid of feathers, and situated just beyond the 

 mi<ldU.> of the wing. The hind wings are short and angular. 



The female is without wings or legs, and is, in fact, hardly more tiian 

 a living egg-sack. When fully mature the pupa splits at the anterior 

 end, and the body of the female protrudes. Without entirely leaving 

 the pupa shell, but dragging it after her, she works her way to tJie, 

 month of the basket, where she awaits the visit of the male, liaving her 

 head at the outlet. 



In what precise manner the act of fertiUzatiou takes place is not well 

 understood,* but as soon as it is accomjdished, the female pushe-; her- 

 self backwards to the farther end of the basket, and, her hinder ex 

 tremity being still within the pupa shell, she juoceeds to till it nearly 

 full of pearly, cream-colored eggs, packed in silk. The vacant si)ace at 

 the end is then filled with a tangle of floss silk, mingled with feather 

 scales, which the mother i)lucks from her own body. When finally 

 her body is entirely withdrawn from the pui)a shell the lips of the 

 y shaped slit at the end snap together, entirely closing the exit. 



The female continues to work her way slowly outward, weaving as 

 she goes a tangle of silk, mingled with scales stripped from her own 

 body. Having filled the entire space within the basket, and lest she 

 should imperil the safety other young by remaining in the case to die, 

 the mother completes the sacrifice by droi)ping from its mouth. Her 

 exhausted body, shorn of its downy covering, falls to the ground, where, 

 naked and defenceless, it becomes a ready piey to ants and other 

 prowlers. 



How wonderlnl an example is here shown of thejiower of the mater- 

 nal instinct, which can thus overpower the instinct of self preservation 

 in an unreasoning insect, and compel her to yield to her offspring, 

 unborn and unseen, a secure retreat, which otherwise in life she never 

 leaves, and from which she conld not be torn except piecemeal. 



The eggs of the Bag-worm hatch in September. The young larvaj 



* See Appendix III. 

 (r)310I 10 



