540 Mr. T. D. A. Cockerell — Descriptions and 



Hab. 60 miles north of Perth, W. Australia ; received 

 from C. French (Nat. jNIus. Victoria, 1). 



Tlie following key separates several similar-looking 

 females : — 



Lower edge of clypeiis with conspicuous teeth ; 



maudibles very broad lucidivenfris, Sin. 



Clypeiis not so, though there is usually a median 



denticle or tooth 1. 



1. Mandibles very lonf^ 2. 



iMandibles broad, relatively short 3. 



2. Mandibles bidentate remeata, Ckll. 



Mandibles tridentate seinilucfuosa, Sm. 



3. First abdominal segment with white hair right 



across revkta, Ckll. 



First abdominal segment with lateral patches of 



white hair suffusipennis, Ckll. 



Halictus musicus, sp. n. 



$ , — Length about 10 mm. 



Rather robust, the abdomeu large ; black, the abdomen 

 with a faint green tint, especially on the first two segments ; 

 head broad ; inner orbits strongly, evenly concave ; front 

 finely punctured, the punctures running into striae, the 

 shiniiig surface visible between ; supraclypeal area and 

 clypeus convex, shining, with sparse distinct punctures ; 

 clypeus wMth a median groove ; tongue broad dagger-shape ; 

 maxillary palpi red apically ; flagellum obscurely reddish 

 beneath; head and thorax with thin dark fuscous hair, but 

 pale ochreous at sides of metathorax, extending up to sides 

 of scutellum ; postscutellum with a large patch of dense 

 orange tomentum, and the same sort of tomentum covers the 

 anterior corners of mesotliorax, adjacent parts of prothorax, 

 and region of the tubercles, making a large elongate patch 

 on each side of the thorax in front ; mesotliorax in middle 

 smooth and subglaucous, sparsely punctured, but densely 

 punctured at sides ; pleura finely and densely striate ; area 

 of metathorax large, bounded by a strong sharp rim, its 

 surface with strong but obtuse irregular rugtc. Legs black, 

 with coarse black hair ; hind femora with a curled soot- 

 coloured scopa ; hind spurs simple ; teguhe black, shining, 

 the anterior part finely roughened and with piliferous pnnc- 

 tures, the anterior margin testaceous. Wings dilute fuscous, 

 nervures and the large stigma reddish ; third s.m. short ; 

 first r. n. reaching extreme basal corner of third s.m. Ab- 

 domen very finely punctured, without hair-bands or patches; 

 at apex and beneath with coarse black hair. 



