TRUE GUESTS, ECTO- AND ENTOPARASITES. 4 ! 9 



other myrmecophiles the reader is referred to my paper on the " Poly- 

 morphism of Ants" (19070). 



The Entoparasites. These constitute an even more diversified 

 assemblage of forms than the ectoparasites. The only entoparasitic 

 Coleopteron, however, is the Stylopid Myrmecolax nietneri, described 

 by Westwood (1861) from the gaster of a Ceylonese ant. The habits 

 of this beetle probably resemble those of the species of Stylops and 

 Xenos which develop in the abdomens of bees and wasps. Among the 

 remaining entoparasites may be mentioned certain Diptera, Hymenop- 

 tera and Nemathelminthes. 



The Diptera are represented by several Phoridae and the Conopid 

 genus Stylogaster. The Phorid Apocephalus pergandei, according to 

 Fox (1887) and Pergande (1900), lays its eggs on. the heads of Cain- 

 ponotus pennsylvanicus workers. The larvae hatching from these eggs 

 enter the cranial capsule through the occipital foramen and feed on the 

 tissues, causing the ant to become very leth- 

 argic. Later the creature literally loses its 

 head, and the larvae pupate and hatch. Per- 

 gande has described the frantic efforts of the 

 ants to rid themselves of these terrible execu- 

 tioners. Coquillet (1907) has recently de- 

 scribed another Phorid, Plastophora crawfordi, 

 which was taken in the act of ovipositing on 

 the head of a Solenopsis geminata in Texas. I 

 have already alluded to the various peculiar 

 Phorids with wingless females (p. 383). They, FlG , 53 pheido- 



too, may be entoparasitic in their larval stages, lo.renus whcdcri from 



. , ,. , , ,. T the nests of Pheidole in- 



but as there is no evidence of such habits, . s tabiiis. (Original.) 

 have placed them among the synceketes. 



As the Conopidae are known to be parasitic in the bodies of adult 

 bees and wasps, it is not surprising to find that some of these flies also 

 attack ants. Bates (1893) observed species of the genus Stylogaster 

 hovering over Eciton armies in Brazil, and Townsend (1897) captured 

 numbers of three species of the same genus in Mexico, while they were 

 following an army of Eciton forcli. There can be little doubt that 

 they lay their eggs on the bodies of the ants and that the larvae are 

 entoparasitic. 



Among the entoparasites is also to be included a number of minute 

 Hymenoptera of the families Braconidae, Chalcididae and Proctotru- 

 pidae. The best known of these is the Braconid Elasnwsoiiia beroli- 

 ncnse, which has been seen by Giraud (1871), Forel (1874), Pierre 

 (1893), Olivier (1893), and Wasmann (18940) ovipositing on the 



