BREEDING BEHAVIOR OF SUCKERS AND MINNOWS. 3! 



tions of the sexes are as indiscriminate as they well can be. We 

 may represent four females of the white sucker or red-horse by 

 the letters A, B, C, D, and four males by the small letters w, x, 

 y, z. Six pairs may be formed with the four males, wx, wy, wz, 

 xy, xz, yz. Assuming that each female spawns once with each 

 pair of males and that her spawnings are distributed at random 

 over the breeding ground we should have some such space- 

 distribution of pairings as shown in Fig. 8. In the hogsucker in 

 which one female pairs with more than two males the relations 

 would be still more complicated. 



No male occupies any particular locus of the spawning ground 

 and attempts to defend it against other males. On the contrary 

 each male is free to wander over the whole spawning ground. He 

 may "pair" in any part of it, for he does not enter into combat 

 with other males but cooperates with them. The female does 

 not restrict her activities to any part of the spawning ground. 

 Were she to do so she would be finally beset by so many males 

 that normal pairing might be difficult or impossible. She does 

 not actively reject any of the males, but when beset by so many 

 that spawning is difficult, she seeks a new locus. This she con- 

 tinues to do until normal pairing becomes possible. She may 

 be said to try various situations of the spawning ground until 

 she finds one in which the conditions permit spawning. This 

 relation of the sexes is neither polyandry nor polygamy. It is 

 promiscuity, corresponding to the hypothetical communal 

 marriage of primitive man. It occurs along with lack of combat 

 amongst the breeding fish. .Where combat occurs, as in min- 

 nows, promiscuity gives place as will be shown in later papers, 

 to a sex relation that approaches polygamy. 



LITERATURE CITED. 

 Boulenger, G. A. 



'04 Teleostei, systematic part, in The Cambridge Natural History, Vol. VII.. 



pp. 541-727. London. 

 Forbes, S. A. and Richardson, E. R. 



'08 The Fishes of Illinois, pp. cxxxi-357, text and atlas of 103 maps, with 40 

 colored plates, 15 black and white plates, and 76 figures in the text. Urbana. 

 Hankinson, T. L. 



'08 A Biological Survey of Walnut Lake, Michigan. A Report of the Biological 

 Survey of Michigan, published by the State Board of Geological Survey- 

 as a part of the report for 1907, pp. 157-288, pi. XIII.-LXXV., 6 text figs. 

 Lansing. 



