PHORIDAE 



495 



and attack living Insects, and even snails, though probably 

 only when these are in a sickly or diseased condition. The 

 metamorphoses of several species have been described/ The 

 larvae are rather slender, but sub-conical in form, with eleven 

 segments and a very small head, amphipneustic, the body behind 

 terminated by some pointed processes. The pupa is remarkable ; 

 it is contained in a case formed by the contracted and hardened 

 skin of the larva ; though it differs much in form from the 

 larva the segmentation is distinct, and from the fourth segment 

 there project two slender processes. These are breathing organs, 

 attached to the prothorax of the imprisoned pupa ; in what 

 manner they effect a passage through the hardened larval skin 

 is by no means clear. Perris supposes that holes for them 

 pre-exist in the larval skin, and that the newly-formed pupa by 

 restless movements succeeds in bringing the processes into such a 

 position that they can pass through the holes. The dehiscence 

 of the puparium seems to occur in 

 a somewhat irregular manner, as 

 in Microdort ; it is never Cyclor- 

 rliaphous, and according to Perris 

 is occasionally Orthorrhaphous ; 

 probably there is no ptilinum. 



The Insect recently described by 

 Meinert as Acnigmatias hlattoidcs'^ 

 is so anomalous, and so little is 

 known aljout it, that it cannot at 

 present be classified. It is com- 

 pletely apterous ; the arrangement 

 of the body-segments is unlike that 

 of Diptera, but the antennae and 

 mouth-parts are said to be like those of Phoridae. The Insect 

 was found near Copenhagen under a stone in the runs of Formica 

 fusca. Meinert thinks it possible that the discovery of the 

 male may prove Aenigmatias to Ije really allied to Phoridae, 

 and ]\Iik suggests that it may be the same as Platypliora luhhocki, 

 Yerrall, known to be parasitic on ants. Dahl recently described 

 a wingless Dipteron, found living as a parasite on land-snails in 

 the Bismarck archipelago, under the name oi Puliclpliora lucifera, 



^ Perris, Ann. Soc. ent. France (4) x. 1870, p. 354. 

 - Ent. Jlcddelelser, ii. 1890, p. 213. 



Fig. 237. — Aenigmatias hkdtoides. 

 X 27. Denmark. (After Meinert.) 



