FLUCTUATING VARIATIONS AND THEIR INHERITANCE 47 



Specifically, the variations by addition consist of : 

 (a) the presence of spurs in unexpected places; such as two short 

 cephalic spurs between the forkings of R 2 and R 3 ^ 4 in a right wing 

 (specimen Sub. 4, H) ; two longer spurs or short branches running 

 from R 3 near its distal end to the wing's costal margin in I right wing 

 (specimen Sub. I, O) ; a spur running proximad from R 2 shortly beyond 

 its forking in I left wing (specimen Sub. 4, L) ; a spur originating 

 from the middle of R 4 and running proximad in I right wing (specimen 

 Sub. 2, I) ; a spur originating from the 2nd anal vein and directed 

 toward the inner margin in I left wing (specimen Sub. 3, C) ; 



Fig. i. Venation of the silk-worm moth, Bombyx mori. 



(b) very short additional cross-veins, as where there is a cross- 

 vein connecting R 3 with R 4 near their distal tips in I left wing (speci- 

 men Sub. i, C) ; or a short cross-vein running cephalad from R 4 to the 

 costal margin in I right wing (specimen Sub. 2,1). 



2. Variation by loss of certain veins entirely or in part. 



The variations are numerous and striking in kind and are repre- 

 sented by many variants. The veins involved include members of the 

 radial, medial and anal series in the fore-wings and the medial, cubital 

 and anal series in the hind-wings. 



The variation in the radial series consists of a "continuous" varia- 

 tion on the part of R 3 . This summary included 46 left and 43 right 



