HTQ DIPTERA—II7ME&0PTERA. 



gives full direcl o which the chief points are that they 



must not be pinned in the middle dorsal line of the thoi 



and that th--\ should not be k i 1 !<•*! with alcohol, while killing 



- 



with p< cyanid< commended. 



Very small Diptera should no1 be killed when they can- 

 not be immediately pinned; too much material should 



illected in the net at one time; and hairy flies should 

 not be taken in the hand to pin, but handled with fine for- 

 ceps, while lacquered-iron needles or lacquered-iron wire 

 should be used for pinning instead of common insect-pins 

 or silver wire (which contain copper and are therefore 

 liable to corrode); wire should be used for all flies under 

 '•'• nun. in length. (Abstract in Psyche, id. 226.)* 



Aquaria are oecessarj for the maintenance of aqu 

 larvae. I:' quantities of swamp-mud ami moss with decaying 

 matter are kept in boxes and jars, multitude.- of small Hies 

 will be hatched out. Leaf-mining and seed-inhabiting 

 species can be treated as M ro-lepidoptera, and earth-in- 

 habiting larvae like ordinary caterpillars. Dung, mould in 

 hollow trees, stem- of plants and to ontain numer- 



ous larvae or i . which must he kept in damp 



Collection and Preservation of Hymenoptera. 



I'll ''ts are exceedingly abundant, and especial at- 



tention should be paid to collecting the smaller spe 

 They should he pinned through the thorax, high upon the 

 pin, and those that are not hairy collected in alcohol. In 

 fact, as much depends on the study of the softer pari 

 the mouth-appendages, specimens of each sp aras 



* Dr Williston tells me thai "Prof. hlik advises oi lii irj sulphur- 

 matches to kill specimens, and the process has » i though I 

 think it is interior to a lined cyanide bottle. Hi ■! tin 

 in w hich there i> Kit an opi ning between the op] - thai \\ ill 

 admit a match. The tlv is put in the box. th< truck and in- 

 serted till ihe sulphur is consumed, then withdrawn and the i 

 fully closed till the tlv is dead." 



