178 H. H. NEWMAN. 



in this instance we would have a solution of the general problem 

 of division that appears everywhere in the field of biology. 



Since the inheritance and distribution of double bands was 

 dealt with in detail in the earlier paper of this series it will not 

 be necessary to refer further to these results. It may be of inter- 

 est, however, to compare the facts as to symmetry phenomena in 

 the two classes of anomaly. Band anomalies are much less 

 numerous than anomalies of single scutes, but they exhibit the 

 same mirror-image phenomena and symmetry reversals that are 

 so frequently seen for double scutes. For details of these phe- 

 nomena the reader is referred to the published account (Newman, 



'15). 



The present study deals solely with scute anomalies, double 



or split scutes of the various types shown in Figs. I to 6. 



3. Frequency and Distribution of Scute Anomalies. 



In the present collections (C and K) there are 700 individuals 

 composed of 140 sets of quadruplets and their mothers. These 

 should constitute for statistical purposes a reasonably adequate 

 sample of the species. 



In the earlier paper of this series (Newman, '15) 23 sets that 

 showed band anomalies in one or more members of a set were 

 dealt with. Many of the individuals (40 in all) had scute 

 anomalies, some with and some without accompanying band 

 anomalies. The remaining 117 sets (585 individuals) treated in 

 this paper contain 199 individuals with double scutes. Whether 

 we figure on the basis of the entire collection or upon the 117 

 sets dealt with in the present paper we find that 34+ per cent, 

 of all individuals have scute anomalies. Add to this 32 (4 + 

 per cent.) individuals that have only band anomalies and we find 

 that about 39 per cent, of all individuals have either band or 

 scute anomalies or both, which is very close to the 40 per cent, 

 arrived at earlier in this paper. Scute anomalies are, however, 

 about eight times as numerous as band anomalies and furnish 

 better material for statistical study. 



4. Sex Distribution of Anomalies. 



Exclusive of the mothers, exactly 40 per cent, of which have 

 anomalies, 22 females and 12 males have band anomalies, and 



