2040 Insects. 



vertical incision.* Males much smaller than the females ; their an- 

 tennae elongate, thirteen-jointed, the joints subarcuate ; the nose 

 usually white or pale yellow at the apex ; the mandibles long, curved 

 and acute at their apex. Abdomen cylindrical, composed of seven 

 segments. 



Sp. 1. Halictus quadricinctus. 

 Meliita quadricincta, Kirby. Hylceus quadricinctus, Fab. ? male. 

 Apis hortensis, Fourcroy ? ? female. Not Apis Jlavipes, Panz. 

 (Walckenaer). Not H. nidulans, Walckenaer. 



Female. — (Length 4| lines). Black ; the face thinly clothed with 

 pale yellow hair ; the labrum has a beard of the same colour ; the an- 

 tennas piceous beneath. Thorax thickly punctured, a few ochraceous 

 hairs thinly scattered on the disk ; the sides and the metathorax late- 

 rally more thickly clothed with pubescence of the same colour ; the 

 tegulse piceous ; the wings subhyaline, the nervures testaceous ; the 

 metathorax rotundate ; the legs nigro-piceous, their pubescence pale 

 luteous ; the tarsi pale rufous. Abdomen fuscous, ovate, convex, 

 shining, minutely and closely punctured ; all the segments have a 

 white marginal fascia, the first interrupted ; the apex clothed with 

 pale ochraceous pubescence, slightly stained with red at the sides of 

 the apical incisure. 



Male. — (Length 4 lines). Black; the face clothed with white pu- 

 bescence ; the apex of the nose pale yellow ; the mandibles very much 

 dilated at the base. Antennas fulvous, as long as the head and tho- 

 rax ; the joints subarcuate; the scape black; three or four of the 

 basal joints fuscous above ; the apical joints pellucid. Thorax closely 

 punctured ; the tegulae testaceous ; the wings hyaline ; the posterior 

 femora, excepting at the knees, and the intermediate and anterior 

 pairs behind, nigro-piceous, otherwise of a fulvous yellow; the tarsi 

 palest. Abdomen linear, shining, closely punctured ; the segments 

 have a white marginal fascia, the first, and sometimes also the second, 

 interrupted ; beneath, the two apical segments are concave. 



* I have used the term incision, but in point of fact what has the appearance of 

 an incision is merely a smooth vertical space between the pubescence which clothes 

 the fifth segment ; the sixth, which is concealed, has also a similar smooth line ; the 

 segment at its apex is produced, and forms an obtusely pointed style ; the margin of 

 the segment is fringed with hairs of the exact length of the style. What can possibly 

 be the purpose of this curious formation I cannot conceive ; it may be connected with 

 some peculiarity in reference to the connexion of the sexes. 



