2 c; 6 The Scottish Naturalist. 



terior stigmatic plates at the sides of the posterior part of the 

 second segment, pale testaceous, neatly and closely fringed ; 

 the hinder end truncate ; the two stigmata situated below the 

 level of the back, only slightly prominent, ferruginous at the 

 tip, which is triply divided ; the truncation minutely subgranu- 

 lose ; a slightly depressed area round the stigmata, surrounded 

 by prominent tubercles, of which there is one on each margin 

 in a line with the stigmata, then three in succession downwards, 

 of which the lowermost is at the end of a raised transverse 

 ridge, which, exclusive of these two lateral ones, bears six 

 tubercles, of which there are four in a row, the two in the 

 middle having behind them two others placed more inwardly; 

 this ridge is followed by a transverse hollow, and this again by 

 a ridge, which has a tubercle at each end ; the anus is a fissure 

 in a hollow lying behind the second ridge; the belly is less 

 curved than the upper surface, and is considerably ridged 

 across. Length, 2yi lines. 



The puparium occurs in the centre of the flowers. As usual, 

 it is a contracted cast of the maggot. 



No. IV.— LEUCOPIS OB SCUBA Haliday (Dipterous parasite of Adelgcs 

 picece and A. corticalis.) 



IN the "Entomological Magazine" (i. 173) Mr. Haliday 

 characterized a small agromyzideous fly, under the name 

 of Leucopis obscura, which he elsewhere (lib. cit. iv. 148) informs 

 us occurred on larch and fir trees, in the month of August, near 

 Holywood in the north of Ireland. More recently Ratzeburg 

 (" Forst-Ins." hi. 170) reared the same fly from the puparia 

 found among the woolly envelope of Chermes ( A delges) picece, 

 and named it Leucopis atratula. ("Ray Soc. Rep. on Zool. for 

 1844," p. 393) ; and it is probably to the same species that 

 Kaltenbach (" Monograph, der Pflanzenlause, i. 200) refers 

 uuder the name of Agromyza chermivora, as proving very destruc- 

 tive to Ch. (Adelges) corticalis. On the 4th of February, I 

 first met with the remains of the empty pupa-cases adhering in 

 profusion to the bark of the trunks of silver firs, in spots 

 that had been previously much infested with Adelges picece, 

 where they had probably remained suspended for years. The 

 Adelges having deserted these places, there were no maggots 



