380 P. W. WHITING. 



The stock 10 female was isolated as a virgin August 1924. 

 After passing through vials a, b, and c she was mated to her sons 

 from a. Daughters appeared in the succeeding bottles. Her 

 progeny totalled 104 males, twenty females, and one immature. 



All the females were set. Eight proved sterile and twelve 

 fertile. In later generations female sterility also appeared. In 

 the total line there were seventy-two females set of which twenty- 

 one failed to produce offspring although they lived the average 

 length of time. 



There were 473 females in the whole line of which one had 

 deficient genitalia, one had tapering antennae and one showed 

 both defects. 



There were recorded only four immature deaths. 



Males of Fi, F 2 , and F 3 from one F 2 fraternity are recorded in 

 Table C. Other F 3 males and males of later generations con- 

 sisted of 489 normal and eight deficient. These eight occurred in 

 Fa after which no more appeared. 



The fraternities of males recorded in Table C evidently fall into 

 at least two groups. 



The six fraternities FiA, F 2 I-L, and F 3 C are the only ones 

 showing males with deficiency both in genitalia and in antennae. 

 They are highly deficient, the ratio averaging 45.8 per cent. 



Deficiencies in antennae and in genitalia are highly correlated 

 in this group for they both occur in 172 cases out of 206. (Vial a 

 of the FI generation could not be included in this total as the 

 deficient were not separated into the three groups.) The 

 remaining ten fraternities of Table C, F 2 A-H, F 3 A-B, with 505 

 males have only thirteen or 2.6 per cent, deficient. None of these 

 is deficient in both characters. 



Frequency According to Age of Mother. 



The males of the six fraternities showing High Deficiency have 

 been summarized with respect to vials in order to test influence of 

 age of mother on ratio of deficient offspring. Table D gives 

 results of this summary and Chart I shows percentage frequencies. 



The rise from a to d is, as in the case of deficiency in genitalia, 

 associated with deficiency in digestive tract, clearly significant. 

 The analogous drop to e is of doubtful significance; the subse- 

 quent rise of no significance. 



