DIMORPHA VERSICOLOR A. 



257 



its head through the opening. It continues by degrees to advance 

 until it is exposed as far as the end of the wing-covers. Fixed in 

 this position, it remains quiet a longer or shorter time till the insect 

 is able to escape, though in two or three instances the pupa had 

 worked itself out entirely free from the cocoon before the moth 

 could be disclosed. Bankes has pointed out (E.M.AL, xxxv., pp. 

 137-139), that, in confinement, the pupa does not always so emerge. 

 Of 15 cocoons, 5 pupae emerged completely from the puparia, 4 

 others stood upright, half out of the cocoons, whilst 6 did not 

 emerge even partially, although ail 15 produced imagines. The 

 reason that 6 did not emerge appeared to be that there was some 

 hard substance, such as a dried leaf or another cocoon, against 

 the emergence-end of the cocoon, sufficient to prevent the pupa from 

 forcing its way through, but not sufficient to prevent the more 

 powerful and better equipped imago from doing so. This was 

 clearly the case with one cocoon in which a hard dry birch leaf 

 was firmly attached to the emergence-end of the cocoon, which 

 had proved too much for the pupa, though the moth had finally 

 freed itself by forcing a passage upwards, just past the edge of the 

 leaf. . . . The pupa, after breaking through the cocoon, soon 

 works its way upwards out of it about as far as the end of the wing- 

 cases ; there it remains upright, generally either for a few days, 

 after which it further advances completely out of its cocoon and 

 lies on the moss for a few days more until the emergence of the 

 moth or else for the whole period (which varies much in duration) until 

 the disclosure of the moth. Bankes then gives the following details : 



Pupa. 



Standing upright half out of 

 cocoon. 



Entirely out of 

 cocoon. 



Imago emerged. 



Remarks. 



3 



February 28th, 4p.n1 





March 10th, circ. 

 1 p.m. 



Lifted out of cocoon, 

 March 2nd. 



3 



March 10th, 2 p.m. 



March nth, 

 4 p.m. 



March 30th, 10.15 

 a.m. 





3 



March 10th, 2 p.m. 





March 30th, 10.15 

 a.m. 



Never came entirely 

 out of cocoon. 



? 



March nth, 9.30 a.m. 





March 31st, 10.30 

 a.m. 



Never came entirely 

 out of cocoon. 



? 



March 13th, 10 a.m. 



March 19th, 

 12.30 p.m. 



March 25th, circ. 

 12.30 p.m. 





¥ 



March 13th, 3 p.m. 



March 20th, 

 10 a.m. 



March 30th, 11.45 

 a.m. 





3 



March 21st, 9.45 a m. 



March 24th. 

 10 a.m. 



March 26th, 10.15 

 a.m. 





? 







March 30th, circ. 

 11 a.m. 



Never came even par- 

 tially out of cocoon. 



? 







March 31st, 10 

 a.m. 



■>■> 11 



3 







March 31st, 10 

 a.m. 



■>■> ■>■> 



? 







April 1st, circ. 

 1 1.30 a.m. 



>i >; 



? 



March 31st, 10 a.m. 





April 3rd, circ. 

 1 1 a.m. 



Never came entirely 

 out of cocoon. 



? 







April 6th, 10.45 

 a.m. 



Never came even par- 

 tially out of cocoon. 



3 







April 7 th, ante 

 8.30 a.m. 



it ■> 



? 



March 31st, 10.30 a.m. 



April 5th, 4 

 p.m. 



April ioth, 9.30 

 a.m. 





