92 
Psyche 
[September 
Figs. 1-9. Metaphase plates from the brain of: (1) Anastrepha ludens; 
(2) A. zuelaniae; (3) A. fraterculus (A. mombinpraeoptans and A. distincta 
are closely similar) ; (4) A. striata; (5) A. aphelocentema ; (6) A. serpentina 
$ showing XiX 2 Y sex chromosomes ; (7) A. serpentina $ showing X 1 X 1 X 2 X 2 
sex chromosomes. (8) Extreme contraction of chromosomes of A. ludens 
resulting from extended pre-treatment in coumarin. (9) Spermatogonial 
metaphase plate from testes of adult A. spatulata. (Magnification of all 
plates 1500X) 
