ISO-AGGLUTINATION AND HETERO-AGGLUTI NA- 

 TION OF SPERMATOZOA. 



MYRA M. SAMPSON, 

 DEPARTMENT OF ZOOLOGY, SMITH COLLEGE, NORTHAMPTON, MASS. 



CONTENTS. 



I. Introduction 2 ^_ 



II. Iso-agglutination 2 ^g 



1. General 268 



2. Material and Methods 260 



3. Iso-agglutination in sea-urchins, Arbacia, Strongylocentrotus 



purpuratus and Strongylocentrotus franciscanus -,- o 



4. Iso-agglutination in Katharina tunicata ,-,j 



5. Iso-agglutination in other Echinoderms and Molluscs 2 ~2 



6. Discussion 273 



III. Hetero-agglutination 274 



1. General 274 



2. Material and Methods 274 



3. Hetero-agglutination of Spermatozoa of Katharina tunicata, 275 



A. Effect of solutions of cytolized spermatozoa of Stron- 

 gylocentrotus purpuratus 9 yt- 



B. Effect of blood of 5". purpuratus and S. franciscanus. 275. 



C. Effect of egg-water of 5". purpuratus and S. franciscanus, 277 



D. Changes in spermatozoa produced by hetero-agglutinat- 



ing substances 277 



E: Discussion 277' 



4. Hetero-agglutination of spermatozoa of 6". purpuratus and of 



5 1 . franciscanus by the blood of Katharina tunicata 279 



5. Hetero-agglutination in other echinoderms and molluscs. . . . 279 



IV. Summary 280 



I. INTRODUCTION. 



The agglutination of spermatozoa reported by Buller (1900) 

 was first adequately described by Lillie (1913). The latter dis- 

 tinguished two types of agglutination differing from each other in 

 cause and in characteristics : iso-agglutination produced by a sub- 

 stance secreted by ripe ova of the same species, and hetero- 

 agglutination by substances present in egg secretions and body 

 fluids of foreign species, Lillie (1914). The characteristics of 

 these types will be considered in the following pages. In this 



267 



