affecting the Potato-crops. 107 



called HoMALOMYiA,* being a section of Antliomyia, The 

 parent fly of our species is exceedingly like Musca cunicularis f of 

 Linnaeus ; still there are differences, and as the larvae are also 

 dissimilar, I have named this Potato-fly 



35. Anthomyia tuberosa.J The male is 2 J lines long, and 

 expands 5^ : it is greyish-black and bristly : the eyes are chestnut 

 colour, naked, approximating on the crown, the inner margin 

 silvery white; antennae drooping, 5 jointed, 3rd joint oblong, 4th 

 a slender elongated basal joint to the longish pubescent seta : 

 thorax with 5 indistinct broad stripes down the back, 2nd and 

 3rd abdominal segments with bright ochreous spots on each side, 

 3rd rarely with 2 similar minute spots : wings transparent, ner- 

 vures dark, the 2 transverse ones not very remote : balancers pale 

 tawny : legs black, base of shanks indistinctly ferruginous (fig. 

 b7 ', X, the natural dimensions), i^sma/e ashy slate colour: the 

 eyes smaller than those of the male and remote; the face not 

 silvery : thorax with 5 distinct broad blackish lines down the 

 back: abdomen ovate- conic, with 2 indistinct ochreous slightly 

 diaphanous spots on the 2nd abdominal segment; in other re- 

 spects this sex is similar to the male. 



The larvae, although indolent, can crawl well ; they are of a 

 dull tawny colour, clothed with long bristly spines, somewhat 

 depressed, elliptical, tapering to the head, which is waved about, 

 and when thrust out is whitish and fleshy, armed with 2 minute 

 hooks like ebony, and there is a little fleshy horn on each side, 

 on the following segment is a spiracle, on either side, surrounded 

 by several stout short rays, the 2 next segments have tubercles on 

 the back, the remainder have a double series down the centre 

 producing bristles, with a double row on each side, and 8 of the 

 segments have a pair of short spines on each beneath, which 

 enable it to walk ; the apex is armed with 6 long bristles a little 

 spiny at the base, but most of the others are naked, or with the 

 slightest appearance of pubescence or little spines at the base ; 

 on the apical segment are 2 spiracular tubes (fig. 58 ; y, the natu- 

 ral size). The pupa being formed within the indurated skin of 

 the larva, it varies from it only in being more convex above, and 

 the fly escapes by a lateral opening in the thorax. 



These larvae and pupae I find occasionally in my garden where 

 cabbages have long occupied the ground, and Dr. Harris remarks 

 that the hairy maggots of Anthomyia cunicularis, or an allied 

 species, live in rotten turnips ;§ they also abound in privies, and 



* Natur. der Inseckten, p. 89. 



t Curtis's Guide, Genus 1287, No. 104. 



% Gardeners' Chron, vol. v. p. 817. 



§ Treatise on Insects injurious to Vegetation, p. 414. 



