54 



HA RD WICKE'S SCIENCE- G OSS IF. 



genus do not spin cocoons as do those of Mycetophila, 

 and other genera. 



Sciophila, Mg., frequents the leaves of trees, 

 herbage and woods. 



Mycetophila, Mg., is generally distributed. West- 

 ward notices the transformations of one or two 

 species of Platyura, Mg. 



Bolitophila^ 3Mg., occurs occasionally in mid-winter 

 if the weather is mild. 



About 150 species of Mycetophilidc; are British, 

 some being tolerably common, but tlie majority are 

 less frequently met with. 



Sciara Thomce, L., Wlk. vol iii. PI. xxx, 3. 

 Platyjira flavipes, Mg., Curt. 134. Macroccra 

 stigma. Curt., Curt. 637. Mycetophila cingulum, 

 Mg., Wlk. vol. iii. PI. xxi. 2. 



3. Bibionidir. 



Most of the Bibionida: are vernal, often appearing 

 in great numbers, the males hovering in the air, 

 their legs vertical. The larvoe are worm-like, living 

 in the earth, on grass roots ; the pupa is naked. 



Antennae four-jointed : Bibio, Geoff. 

 Antennae eleven-jointed. 



Palpi long : Dilopluis, Mg. 



Palpi short : Scatopse, Geoff. 



Bibio Marci, L. , a rather large black fly, appearing 

 in IMarch ; abdomen elongated, legs rough and 

 hairy; Avings clear in <?, brown in $ : transforma- 

 tions known ; long 8 mm. 



Dilophus febrilis, L., is a smaller species, not un- 

 like the above, and is sometimes taken in winter. 

 In its larval state it infests the potato ; a correspond- 

 ent of mine bred it from Calceolaria. 



Scatopse notata, L., is a small black fly, often 

 common in houses in the summer and autumn ; the 

 wings are large and quite clear, the legs rather short, 

 long 2-3 mm. 



Bibio venos2ts, Mg., Curt. 138. B. Marci, L., 

 Wlk. iii. PI. xxx. 5. Scatopse bifilata, Hal., Wlk. 

 iii. PI. xxiv. 6. 



4. Siinitlidci:. 



These are often known as "sand flies" [Simuliutn, 

 Lat.), and sometimes are as numerous and as great a 

 source of annoyance as mosquitoes. The larvas of 

 some species are aquatic, the wings of the imagos 

 emerging from the pupa case beneath the water. 



Only two species are British ; both uncommon. 

 Walker gives five species (three being repudiated by 

 Verrall), whilst Curtis mentions no less than thirteen 

 as indigenous. 



5. Chironomidce. 



A large number of species are British, but they 

 have not yet been satisfactorily worked out. The 

 species in most instances are fairly distinct, but 

 owing to the lack of published matter, exceedingly 

 difficult to identify. 



Walker describes the larvas of two common 

 species. 



They are known as " mosquitoes," and are small 

 delicate flies, with clear wings and indistinct vena- 

 tion, the males having large feathery (plumose) 

 antenna. No ocelli. They are common of an 

 evening, usually hovering in small swarms under trees 

 and over bushes. 



Chironotnus pliimosus, L., is the common "mos- 

 quito," the larva being aquatic, blood-red, living in 

 stagnant water. 



Winnertz has elaborately monographed the genus 

 Ccraiopogon, Mg. (known as midges). 



The two principal genera may be separated 

 thus : — 



Metathorax produced over base of abdomen : Chironoinus, 



IMg. 

 Metathorax short, descending to the posterior coxae : 



Ceratopogon, Mg. 



The bodies of some species of Taiiypus are almost 

 transparent, and most of the species have spotted 

 wings. They are distinguished from Chirojwmus by 

 the apex of the discoidal cell giving forth four veins 

 instead of three. 



Clunio marinus, Hal., a rare species, has coria- 

 ceous wings, and is found on the sea-coast . 



Chironoiims pliunosus, L., Wlk. iii. PL xxx. 4. 

 Tanypiis nebiilosiis, Mg., Curt. 501. 



6. Orphncphilida:. 

 Orphnephila icstacca, Ruth., has occurred in 

 Britain. It is a rare species. 



7. PsycJiodidce. 



These are small, blackish-grey, pubescent, moth- 

 like flies, with very large scaly wings fringed at the 

 edge, and pointed at the tip. The larva; are aquatic. 

 (Two common species live in cowdung. ) One species, 

 P. phalcenoidesy L., being very common, occurring 

 in London all through the summer months ; easily 

 recognised by its zigzag movements on the windows. 

 P. sexpiuictata, Curt., is not uncommon, being easily 

 recognised by the six small but distinct black spots 

 along the front border of each wing. One or two 

 species appear in mid-winter. 



P, sexpunctata. Curt. 745. 



8. CuUcidic. 



The too well-known "gnat," Culex pipiens, L., is 

 the type of this family. 



The larva: (figured by Westwood) are aquatic, and 

 active, the eggs being glued together in the form of a 

 boat. Degeer and others have well worked out the 

 life-histories of several species. The pupa is active, 

 but takes no nourishment. 



The Culicida: may easily be recognised and 

 separated from the Chironotiiidcc, to which they bear 

 some resemblance, by their wings being fringed, and 

 the venation being more distinct and more compli- 

 cated. 



