26 ANIMAL AGGREGATIONS 



the same sort of value, if such it can correctly be considered, in the 

 other cases cited by Deegener, such as the amphibians, Hylodes 

 lineatus and Pipa pipa. 



(2) Patropaedia of this sort are thought by Deegener to be illus- 

 trated by the relations in the obstetric toad Alytes, in which the 

 male carries the strings of eggs twisted about his legs, and in Rhino- 

 derma darwini, a small cricket-like frog of the moist beech forests of 

 Chile. The male of the latter species takes the fertilized eggs and 

 crams them into his singing pouch, which becomes greatly enlarged 

 during the breeding season. Here they develop and transform, hop- 

 ping forth from their father's mouth as fully developed small frogs 

 (Barbour, 1926). 



2. Secondary societies are those in which the individuals are not 

 together from the very beginning, or at least those in which the 

 primary social group becomes modified by secondary additions. 



a) Sexual societies of the Protozoa are such as are shown in ciliate 

 conjugation. 



b) Connubium simplex of the Metazoa is a grouping in which mat- 

 ing occurs between animals of the same species but of different sexes, 

 or between hermaphroditic animals. 



(i) Polygamy includes polygyny, or the mating of one male with 

 more than one female, as in polygynous birds, such as the domestic 

 fowl, and in many mammals; and polyandry, in which several males 

 mate with a single female without the female being free to all males. 

 Among Deegener's examples are the cases of double copulation in 

 insects. In the case of Alcippe, a barnacle, the females as a rule live 

 near each other, and from three to twelve dwarf males join each 

 female and remain with her during their lives. Alverdes (1927) states 

 that this sort of relationship is rare, but adds the case of Boncllia, a 

 worm of which more will be said in a later section, and with which as 

 many as eighteen males attach themselves to a given female and 

 remain so for extended periods. Polyandry has also been observed 

 among some spiders. 



(2) Monogamy is fairly widespread, at least in the form of seasonal 

 pairings. It is found among beetles, as for example, the monogamous 



