Aphiochaeta. 259 



Length 1,3 to fiilly 2 mm. 



As seen this species varies to no small degree and especially 

 as regards the breadth of the frons, the size of the hind tibial bristles, 

 the length of costa and of costal cilia and also as regards the size of 

 the hairs on the sides of second abdominal segment. In its typical 

 forms the species will, however, be known by the relatively narrow 

 frons, the small siipraantennals and the bristles on hind tibiæ, and 

 the male by the small, short-bristled palpi. I possess some specimens 

 with large and nearly equal supraantennal bristles and in the male 

 witli palpi of ordinary size and armature which, however, I cannot 

 satisfactorily distinguish from rata^ and one or more related species 

 perhaps still exist here. 



A. rata is one of the most common species in Denmark and occur- 

 ing all over the country; it occurs during the whole season, my dates 

 are ^U — ^Ve; I have taken it in copula on Vs and ^V?. I possess spec- 

 imens bred from larvæ in dead Lepidopterous larvæ from North Sea- 

 land, from larvæ taken in a dead Orgyia antiqiia at Bernstorff on 

 Vil and developing on ^Vs next year, from larvæ taken in a dead 

 Prionus coriarius in Hareskov in October, developing on ^'^U — '^'^U 

 next year, and from piipæ taken in the nest of a chaffmck at Strandby 

 on Lolland on ^|^ and developing on ^7?, and fmally bred from a nest 

 of Vespa vulgaris taken at Hillerød on ^^/g, the imagines developing 

 on ^/e next year (Kryger). I have also seen a specimen bred from a 

 pupa fonnd at Damhusmosen in flood refuse in April 1878 and devel- 

 oping soon after (Schlick), and this is, as far as I know, the first time 

 the species has been found in Denmark. Schmitz 1. c. mentions it 

 from nests of Bombus and says it is parasitical, and it is once recorded 

 as bred from a living larvæ of Clerus formicarius (Schmitz, Zool. 

 Jahrb. Syst. 37, 1914, 553), but I believe it is more probably a scav- 

 enger. 



Geographical distribution: — This common species is at present, 

 besides from Denmark, only recorded from England and Holland, 

 but no doubt it has a much wider geographical range. 



Remarks: Wood described 1. c. a species albicans which should 

 be nearly related to rata^ the separating characters are for a great 

 deal such towards which the varying characters of rata tends; Schmitz 

 has 1. c. noted this, and I quite agree with him when he says that 

 specimens of rata often show one or other of the characters given for 

 albicans; I therefore think it doubtful whether albicans is more than 

 a variety of rata. 



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