NOTES ON BREEDING ODONTOPERA BIDENTATA. Ill 



experiment proved that larvse fed up much more rapidly in these tins 

 than in any other form of breeding cage. 



The floor of the tin is covered with one inch of moss fibre, diiihtlij 

 damp, with a piece of paper on top, leaving a margin, and the twigs of 

 privet or apple laid on top. 



Although it is necessary to open them at least every 48 hours, one 

 or two minutes sufJtices to change the food, and the mortality was not 

 above 3%, including some weak families. Ten to 35 larvae pupated in 

 each tin, and in many cases mortality was nil, the larvje being put in 

 when half grown. 



{(■) Slccriiui. — Ova, or very young larvfe, were sleeved on privet and 

 apple. Mortality less than 2%, except from parasites. As rate of 

 (growth in the various families and within a family is so variable, 

 frequent watching is necessary in order to remove full fed larva? to 

 material suitable for pupation. 



H. Coldiir (if iMnue. — It was interesting to note the variation of 

 colour due to environment, as proved in Professor Poulton's classical 

 experiments. The red of PrnnnR pissardii. twigs, the beautiful green 

 of apple shoots, the gray brown or black of apple twigs, and the brown 

 of moss fibre, were all faithfully imitated. 



9. liiiltits of Larva-. — They feed only at night, eating voraciously 

 and moving actively. Characteristic " stick" habits by day. Not only 

 a general feeder, but enjoys a mixed diet, or after feeding for weeks on 

 one food-plant readily changes to another. Occasionally cannibalism 

 has been suspected, but never actually observed, and certainly does not 

 occur if food supply is plentiful. It is very probaljle that various 

 characteristics and habits of larvje run in families, and efforts have 

 been made to collect evidence on this point. 



10. I'lijiation. — Larvae prefer moss fibre to any thing else in my 

 experience. It should bo sieved to remove dust and very fine particles. 

 If cokernut fibre is used many imagines are strangled and fail to 

 emerge from cocoons. Althoutijh dead leaves always littered the cage 

 floor, larvfe used them for pupation in only about ten out of over 2500 

 observed cases. 



11. i'ocoim is made of granules of moss fibre, and is lined by a 

 loose meshed network of strong, thick strands of silk. The cocoons 

 are usually collected in bunches, but I have never found two pupte in 

 one cocoon. If a larva has no available material for cocoon, it spins a 

 slight net of fine closely meshed silk. If left late in a sleeve, frass is 

 utilised in forming the cocoon. 



12. I'lipa. — Larval skin is shed in 3-5 days after the cocoon is 

 foriueii. The pupa moves if touched at any time throughout the 

 winter. If kept indoors, even in a non-heated room, emergence of the 

 imago occurs frequently in December, January, and February, especially 

 of the melanic form. In this observation I am supported by several 

 entomological friends. Curiously enough 



13. F(irciii(/ during the autumn does not hasten the emergence. 



