POLYMORPHISM. 



99 



22. The plercryate, " replete," or " rotund," is a worker, which in 

 its callow stage has acquired the peculiar habit of distending the gaster 

 with stored liquid food ("honey") till it becomes a large spherical 

 sac and locomotion is rendered difficult or even impossible (Figs. 218 

 and 219). This occurs in the honey ants (some North American species 

 of Myrmccocystus, some Australian Melophorits and Camponotus, and 

 to a less striking extent in certain species of Prenolepis and Plagiolepis}. 



23. The ptcrergate is a 

 worker or soldier with ves- 

 tiges of .wings on a thorax 

 of the typical ergate or 

 dinergate form, such as 

 occurs in certain species of 

 Mynnica and Cryptocerus 

 (Fig. 63). 



24. The mermithergate 

 is an enlarged worker, pro- 

 duced by Menu is parasit- 

 ism and often presenting 

 dinergate characters in the 

 thorax and minute ocelli in 

 the head (Fig. 254, B, C). 



25. The phthisergate, 

 which corresponds to the 

 phthisogyne and phthisaner, 

 is a pupal worker, which in 

 its late larval or semipupal 

 stage has been attacked and 

 partially exhausted of its 

 juices by an Orasema larva 

 (Fig. 252, B and C). It is 



characterized by extreme 



stenonoty, microcephaly and microphthalmy, and is unable to pass on 



to the imaginal stage. It is in reality an infra-ergatoid form. 



26. The gynandromorph is an anomalous individual in which male 

 and female characters are combined in a blended or more often in a 

 mosaic manner (Figs. 64 and 65). 



27. The ergatandromorph (Fig. 66) is an anomaly similar to the last 

 but having worker instead of female characters combined with those 

 of the male (Wheeler, 1903^). 



It is usually conceded that the fertilization or non-fertilization of 

 the egg of the social Hymenopteron determines whether it shall give 



FIG. 60. PhcidoJc borinquenensis of Porto 

 Rico. (Original.) a, Soldier; b, same in profile; 

 c, worker. 



