PSYCHOLOGICAL AND ETHICAL ASPECTS. 265 



A grade higher, true sexual union begins to appear. But 

 at first this simply occurs between any male and any available 

 female. The union is physiological, not psychological ; there 

 is no genuine pairing, and it would be folly to use the word 

 love in such cases. 



Gradually, however, for instance among insects, the sexes 

 associate in pairs. There is some psychic sexual attraction, 

 often accompanied with no little courtship, but much more im- 

 portant is the occasional maintenance of the association for a 

 lengthened period. There may even be co-operation in work, 

 as in dung rolling beetles such as Afeuc/ius, where the two 

 sexes pursue their somewhat disinterested labours together. 

 The male and female of another lamellicorn beetle {Lcthrus 

 cephalotes) inhabit the same cavity, and the virtuous matron is 

 said greatly to resent the intrusion of another male. As degene- 

 rate offshoots from the path of psychic progress, or as illustra- 

 tions of the predominance of merely physical attraction, one 

 must regard such prolonged associations of the two sexes as are 

 seen in the formidable parasitic worm Bilharzia^ where the 

 male carries the female about, or in some parasitic crustaceans 

 where the positions are reversed (see figs. pp. 17 and 71). 



Among the cold-blooded fishes, the battles of the stickle- 

 back with his rivals, his cai)tivating manoeuvres to lead the 

 female to the nest which he has built, his mad dance of 

 passion around her, and his subsequent jealous guarding of the 

 nest, have often been observed and admired. In one of the 

 sunfishes the male and female alternate in guarding the ova. 

 The monogamous habits of the salmon, and the frequently fatal 

 contests between rival males are well known. Carbonnier has 

 beautifully described the elaborateness of sexual display and the 

 ardency of passion in the male butterfly-fish, and also in the 

 rainbow-fish of the Ganges. 



The amatory croaking of frogs, the love-gambols of some 

 newts, the curious parental care of some male amphibians 

 mentioned in the preceding chapter, and the like, illustrate the 

 continuance of more than crude physical attraction between the 

 sexes. It is indeed only in sexual and reproductive relations 

 that the amphibians seem to wake up out of their constitutional 

 sluggishness. 



In regard to reptiles, little is known beyond the exhibition 

 of sexual passion and the jealous combats of rival males. Yet 

 Romanes refers to the interesting fact that when a cobra is 



