ATTTHORS ABSTRACT OF THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE SEPTEMBER. 



SYNAPSIS AND CHROMOSOME ORGANIZATION IN 



CHORTHIPPUS (STENOBOTHRUS) CURTI- 



PENNIS AND TRIMEROTROPIS 



SUFFUSA (ORTHOPTERA) 



D. H. WENRICH 



Department of Zoology, University of Pennsylvania 



THREE PLATES 



CONTENTS 



I. Introduction 472 



II. Observations 474 



A. Chorthippus (Stenobothrus) curtipennis 474 



a. Introductory statement 474 



b. The post-spireme chromosomes 475 



c. Synapsis 476 



d. Chromatid movements 479 



e.. The planes of the first division 480 



f. The apical constrictions and the chromomere-vesicles 481 



g. The accessory chromosome 483 



h. Summary 483 



B. Trimerotropis suffusa 484 



a. Introductory statement 484 



b. The post-spireme chromosomes 484 



c. The evidence on synapsis 486 



d. Chromatid movements 487 



e. The planes of the first division 490 



f. Additional observations on organization 492 



g. Summary 493 



III. Discussion 494 



A. Synapsis 494 



B. Pre-reduction vs. post-reduction 498 



C. Chromosome organization 505 



a. Atelomitic chromosomes 505 



b. The chromomere-vesicles 507 



D. Summary of conclusions 509 



IV. Literature cited 510 



471 



