NOTES ON BREEDING ODONTOPERA BIDENTATA. 113 



experiment ; and lack of this precaution is a common cause of failure 

 in similar ventures. 



20. Parositcs. — Of these (i.) I>nrkha)isenia psendospretella was the 

 most harmful. In spite of carefully baking the mossfibre used, loss 

 was caused each year by the larvie of this moth eating the bidentata 

 puptp. The only consolation was afforded by remarkable cases of 

 assembling displayed by the parasite. 



(ii.) Four cases of Ichneumon appeared. 



(iii.) Of the coleoptera a cannibal species slaughtered fifteen larvae 

 and pupfe in two sleeves. 



(iv.) l'!anri'(/s are under my suspicion, but several prolonged 

 attempts to persuade them when under observation, to devour larvae 

 or soft pupae failed. 



(v.) Mice accounted for 300 pupaj in 1912-13, but fortunately did 

 not break the generations. 



21. iMhellin//. — Every cage or box was labelled inside and out. 

 The orthodox method was used ; thus : — 



10-4 = family derived from the 4th pairing in 1910. 

 1334= „ „ „ „ 34th „ „ 1913. 



(See diagrams). 



22. Double Brood.- — Family 13*20 consists of about 100 members, 

 which fed as larvae during May, June, July, 1913, the last to pupate 

 going down on July 31st. Although kept in a cold room, a few 

 imagines emerged in December, and on January 8th. 1914, two 

 emerged and paired. The resultant ova. Family 14*2, were divided 

 into : — 



(i.) Batch A, kept in a room at 45°F-55°F. They hatched on 

 February 1st, and the larvag were incubated at 65°F. They pupated 

 (about 50) from March 12th-28th. Pupae were forced in a friend's 

 greenhouse and imagines emerged in July. Two paired July 20th 

 and the resultant ova, 15*1, hatched August 10th. My wife, although 

 absolutely inexperienced in entomology, rose to the occasion, and 

 took charge of these (and of all my other specimens) from this date. 

 The larvae were kept in an ordinary room, fed on apple and privet 

 and about 50 safely pupated September 12th-October 3rd, thus 

 completing the double brood. 



(ii.) Batch B ova of 14-2 were left in the cold room. They did 

 not hatch till February 22nd, the temperature then being 44°F. 

 During the next few w^eks they lived in 42°F.-53°F. On April 2nd 

 they were sleeved in the garden, survived several nights frosts and 

 pupated out of doors in the first twelve days of Ma}'. 



Although still left out of doors, some of the imagines appeared in 

 the first three weeks in September. Two emerged October 9th and 

 paired. Resultant ova, 15-2, brought indoors, and kept in a living 

 room. They hatched November 6th, and fed on evergreen privet, 

 pupated in the last week of January and first week of February, 1915. 



Thus bidentata can with care, be made to withstand various dis- 

 advantages of parentage and environment. 



23. Breedimj black fonns. — Finally, with regard to the statement 



