TRÄGÅRDH, TILL KÄNNEDOMEN OM DIPTERLARVERNA, 2. 13 



the Experimental Station, on Epichloé typhina attacking 

 Phleum pratense and Dactylis glomerata. The efforts to breed 

 the species were fruitless, but Mr. Collin, the wellknown english 

 dipterologist, on hearing of the characteristic habits of the 

 larva immediately identified it and gave me the references 

 necessary. Several authors identify Anthomyia spreta with 

 Anthomyia radicum, but to judge from Hewitt's description 

 of the latter larva it is easily distinguished from the former 

 species; this fact together with the entirely different habits 

 of the larvae seems to justify the opinion of Schiner, who 

 considered them two different species. The main features 

 of the life-history were recorded by Girattd (1872), but his 

 description of the larva is very short and the changes which 

 take place in the mouthparts and the cephalopharyngeal 

 skeleton during the growth of the larva were not known to him. 



Development: As is the case in all Muscid-larvse 

 the development of which has been investigated, there are 

 also in A. spreta three instars, which differ greatly one from 

 another as regards the mouthparts and cephalopharyngeal 

 skeleton as well as the spirades. 



l:st instar (Figs. 2 — 4). Viewed from below the head of 

 the larva strikingly resembles that of a whale-russ. The upper 

 margin of the mouth-aperture is covered by a narrow, black- 

 coloured, W-shaped dentate plate with 34 teeth; the mandibles 

 are narrow and pointed thin blades, in outline of rhomboid shape. 

 Their anterior ventral edge is slightly concave; the dorsal one 

 almost straight; the posterior upper angles are bj^ means of a 

 pair of narrow bars (mstj) connected with the median tooth (t); 

 the middle of the posterior ventral edge is, on the other hand, 

 connected with the anterior tip of the lower pharyngeal sclerites 

 by means of a pair of bar-shaped sclerites, which are fused with 

 the mandibles for a short distance, and diminish gradually 

 in width backwards (mst 2 ). The median tooth is a short 

 oval plate, in its posterior half provided with two small, ring- 

 shaped, thinner spöts, one behind the other; it is through 

 a narrow, neckshaped portion connected with the two long 

 anterior pharyngeal sclerites (f ) which taper gradually forwards 

 and are conspicuous through their great length; of the pos- 

 terior pharyngeal plates (öf , uf ) , which together with the anterior 

 ones form a stirrup-shaped structure, the dorsal ones are 

 short er, narrower and more pointed t han t lie lower ones, 



