NEMATOCERA. 89 



so pale. $ resembles <?, only the antennae are 21-22-jointed. 

 Ovipositor yellowish-white ; long ; no lamellae. After death the 

 colours turn browner and the white hairs less silvery. PI. ii. (2). 



L. albipentiis, Mg. 



The larvce live between the scales of the galls produced by C. 

 rosaria on Salix alba. 



Imago. — Deep black ; wings limpid and hairy, gray at the tips, 

 with veins and cilia black ; a small white spot is present at the tip 

 of the first longitudinal vein, on the costa. Legs piceous, stout 

 moderately long.* 



L. stygia, Mg. 



This is a brownish species, yellowish on the ventral surface ; black 

 antenna ; densely pubescent dark-gray wings. Legs long and stout, 

 white in certain lights. Metatarsus longer than any of the following 

 joints. Life history unknown. 



Z. obfuscafa, Mg. = Cecidomyia ob/uscata, Walker (p. 86). 



Testaceous ; black head and antennse. Thorax brownish. Legs 

 as in species above, but with brown bands on the tibiie and tarsi. 

 Walker says the larvae have been observed by Kaltenbach to feed on 

 the thistle. 



Z. fuliginosa, Steph. 



Habits unknown. Recorded in Stephen's " Illustrations of British 

 Entomology," 1846 (p. 42, Fig. 4). 



Z. pusilla, Mg., and berberina, Schrk., are two reputed species in 

 the English fauna. 



The family just passed over in this chapter is seen to be one of 

 great importance, on account of its containing so many insects that 

 are injurious to plant life, especially two {C. destructor and D. tritici) ; 

 many of the others are injurious in a less extent. Considering, then, 

 the destruction caused by these small and insignificant-looking flies, 

 it is strange that they have passed unnoticed so much in England ; 

 scarcely any local lists contain more than one or two species out of 

 the great number already recorded in Britain. Dale, for instance, 

 only records C. tritici from W. Cornwall ; only three or four are 



* Sys. Besch. der b.e.;r., Insekten, A. 1818, T. i., p. S9, pi. iii., fig. 5. 



