HEMICHROA ALNI. 5 



Nematus alni, Dbm., Clavis, 25,26 (lar.). 



Hemichroa alni, Ste., 111., vii, 55, 1, pi. xxxviii, fig. 2 ; Smith, 



Ent. Ann., 1864, 113; Cam., Fauna, 



27, 1; Andre, Species, i, 94; Cat., 



11,* 1. 

 Dineura Htg., Blattw., 228, 6 ; Evers., Bull. Mosc., xx, 



22, 4; Yoll., Tijd. Ent., viii, 84-88, 



pi. v; Tasch., Hymen. Deut., 23; 



Kalt, Pfl. 620. 

 Leptocercus Thorns., Hym. Sc., i, 77, 1 ; Brischke., Beob. 



ii. Blatt. u. Holzwesp. (2), 38, Taf. i, 



fig. 11 (lar.). 



Black, covered with white pile. Head, mesonotum with scutellum, 

 anterior tibiae and tarsi red ; palpi pale ; cerci large, pale red ; mandi- 

 bles brownish. Wings hyaline; lanceolate cellule clouded; nervures, 

 costa, and stigma black. 



The $ has the antennae brownish on the under side, the thorax with- 

 out any red ; the legs reddish-yellow, black at the base ; wings smoky ; 

 anal appendages reddish ; the apical abdominal segments piceous in the 

 middle, with the apex slightly incised. 



Length 3^4 lines. 



Ab. a. ? Antennae reddish, except at the base. 



b. Wings infuscated throughout. 



c. with smoky blotches. 



The larva lives usually on the alder, but I have also 

 bred it from birch. The eggs are laid on the leaf 

 stalk, and the larva lives singly, or at most in twos or 

 threes on the leaf, eating irregular holes in the surface, 

 leaving the veins untouched. When young it is green, 

 except that the head is darker. When mature the 

 head is reddish, or dark reddish-brown ; the eye spots 

 black, and the mouth brown. The upper part of the 

 body is dark green, the skin rugged and somewhat 

 obscured with black ; the lower part is bright green ; 

 often it is pale, almost white. The segmental divisions 

 are well marked. The legs are green, with a tinge of 

 red ; the claws brown, claspers green. When full 

 fed and about to pupate, it becomes pale green, 

 pale orange on the first and on the two or three anal 

 segments. 



The cocoon is spun in the earth ; it is single, oblong, 

 and dark brown. The pupa is green. Monoblastus 

 erythropygus, Him., and Cteniscus sexcinctus, Gr., are 

 its parasites. 



