316 SILK-MOTHS. Cha- . VIII. 



preservation of a particular stock of bees. Mr. Lowe ^'^ pro- 

 cured some bees from a cottager a few miles from Edinburgh, 

 and perceived that they differed from the common bee in the 

 hairs on the head and thorax being lighter coloured and more 

 profuse in quantity. From the date of the introdixction of 

 the Ligurian bee into Great Britain we may feel sure that 

 these bees had not been crossed vsdth this form. Mr. Lowe 

 propagated this variety, but unfortunately did not separate 

 the stock from his other bees, and after three generations the 

 new character was almost completely lost. Nevertheless, as 

 he adds, " a great number of the bees still retain traces, 

 though faint, of the original colony." This case shows us 

 what could probably be effected by careful and long- 

 continued selection applied exclusively to the workers, for, 

 as we have seen, queens and drones cannot be selected and 

 paired. 



SiLK-MOTHS. 



These insects are in several respects interesting to us, more 

 especially because they have varied largely at an early period 

 of life, and the variations have been inherited at correspond- 

 ing periods. As the value of the silk-moth depends entirely 

 on the cocoon, every change in its structure and qualities has 

 been carefully attended to, and races differing much in the 

 cocoon, but hardly at all in the adult state, have been pro- 

 duced. With the races of most other domestic animals, the 

 young resemble each other closely, whilst the adults differ 

 much. 



It would be useless, even if it were possible, to describe all 

 the many kinds of silk-worms. Several distinct species exist 

 in India and China which produce useful silk, and some of 

 these are capable of freely crossing with the common silk- 

 moth, as has been recently ascertained in France. Captain 

 Hutton*^ states that throughout the world at least six species 

 have been domesticated ; and he believes that the silk-moths 

 reared in Eiirope belong to two or three species. This, how- 



«* ' The Cottage Gardener,' May, *^ ' Transact. Entomolog. Sue.,' 3rd 



1860, p. 110; and ditto in 'Journal series, vol. iii, pp. 143-173, and pp. 

 ofHort.,' 1862, p. 242. 295-331. 



