S. A. Arendsen Hein 



2&7 



g. The Elytra. 



The variations in these organs presented themselves mainly : 



1°. -4.9 a shoHening or a lengthening of one or of both elytra. 



The elytra look perfectly normal for that matter, and do not suggest 

 that the anomaly has arisen from a developmental disturbance, as many 

 other reductions do which are accompanied with deformities of the 

 wings. 



No. 19. Quite an exceptional case is the shortening of one elytron 

 only ; the abdomen on that side is then not wholly covered (Fig. 12 a). 



Fig. 12. 



No. 20. More than once both wing-covers were found shortened. 



No. 21. The case of the elongation of both elytra shown in Fig. 12 6^ 

 is rare. 



No. 22. So also is that of one elytron being prolonged as in Fig. 12 6l 

 (The dotted line in the figures indicates the outline of the abdomen.) 



2°. As a divergence of the median elytral edges.. 

 Normally the median elytral edges touch each other in their whole 

 length. 



