Phoridae. 81 



thorax is somewhat reduced. Also the abdomen is altered, the tergites 

 being small and rudimentary, and in a couple of genera the abdomen 

 is quite membraneous; it sometimes bears rows of long bristles, It 

 will be seen that the ciirious aberrations, with the sole exception of 

 Aptinandria, mainly or only concern the females, and the forms in 

 question are in most cases nyrmecophilous or termitophiloiis. In 

 many of these genera a curious feature is described, consisting of 

 an opening or excision at the base of the fifth abdominal segment 

 (perhaps sometimes the fourth) in the female, covered by a semi- 

 circular cover, thus a similar feature to that found in Metopina among 

 European forms; it is thought to be in connection with a kind of 

 gland; I think the curious small excision at the base of the sixth 

 segment in Aphiochaeta, mentioned below under this genus, is some- 

 thing similar , though here occurring on another segment, and so is 

 perhaps also the feature found on the fifth segment in Phalacroto- 

 phora and in Chaetoneurophora thoracica. Schmitz thinks it possible 

 (Tijdschr. voor Entom. 59, 1916, LIX) that this organ is no gland, 

 but may be of use by the opening of the pupa-case; in thoracica I 

 think that the formation is in some connection with the copulation 

 (see under this species). Some of the degenerate forms (Wandolleckia) 

 are recorded to show the same curious imaginal development with 

 stenogastric and physogastric individuals as mentioned above for 

 Termitoxenia (Schmitz, Zool. Mededeel. 'sRijks Mus, Lejden II, 

 1915, 1). 



In the subfamily Platyphorinae the species are small, of a broad 

 and flat shape. The head is broader than high, excavated behind 

 and lying close to thorax; frons broad, always broader than the eyes 

 taken together, without bristles or with single bristles at the margins, 

 Eyes of normal size to small or very small, especially in the female, 

 bare or pubescent; ocelli present in the male and in the females with 

 wings, but absent in the unwinged females, Antennæ inserted low 

 down, near the oral margin, The oral aperture relatively small so 

 that broad, horizontal jowls are present; a row of confluent oral and 

 genal bristles stretching from the oral aperture to the Iower part of the 

 eye. Thorax broad and flat, especially in the female, without dorso- 

 central bristles; scutellum present in the male and in the females 

 with wings, it is short and broad, with or without marginal bristles; 

 in the wingless females it is absent, Mesopleura wedge-shaped, pres- 

 enting a dorsal and a ventral surface meeting in a sharp longitudinal 

 lateral margin; the dorsal surface partaking in the formation of the 



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