Mr. T. D. A. Cockerell on new Species of Perdita. 493 



yellowish beneath; tubercles and face-marks cream-colour; 

 legs yellow, tarsi brownish ; a patch at end of hind femora, 

 hind tibiae, and tarsi brown. Head subquadrate, but not 

 particularly large, broader than long ; clypeus low and broad ; 

 mandibles cream-colour, black at tips and reddish just before 

 tips ; labrum and clypeus cream-colour, the latter with the 

 usual dots, and two longitudinal stripes vaguely indicated by 

 brownish stains ; supraclypeal mark present, produced above 

 for a short distance as a narrow stripe or line, separated 

 below from the clypeus by a distinct interval ; dog-ear marks 

 present but extremely minute, not nearly touching the clypeus ; 

 lateral marks consisting of a broad stripe below, abruptly 

 narrowing just above the level of the antennal sockets to a 

 narrow stripe, which continues along the orbital margin a3 

 far as the level of the middle ocellus ; scape with a yellow or 

 cream-coloured stripe beneath ; fiagellum very dark brown 

 above, somewhat paler beneath ; face and front without any 

 conspicuous pubescence ; cheeks very thinly pubescent ; 

 front granular. Mesothorax very shiny, very thinly pubes- 

 cent, with a median furrow on its anterior half ; metathorax 

 bluer ; pleura wholly dark ; tegulae transparent, with a cream- 

 coloured spot ; stigma pale brownish, with a darker margin ; 

 nervures brown, marginal cell obliquely truncate, appen- 

 diculate ; second submarginal narrowed about one half to 

 marginal, third discoidal distinct. 



Var. a. — Hind border of prothorax yellow ; second abdo- 

 minal segment with a short transverse yellow stripe near the 

 base ; ventral surface of abdomen clear yellow. 



Bab. S. Jose" de Guaymas, Mexico, April 10, 1898 {L. 0. 

 Howard). 



Named after the most active student of American Hymeno- 

 ptera. In my table of Perdita'm Bull. Denison Lab., P. Ash- 

 meadi comes near to $ crassiceps, but it differs from that in 

 many particulars. The var. a resembles rather tarda, but is 

 easily separated from it. 



Perdita sonorensis, sp. n. 



$ . — Length about 6 millim. 



Black, with a metallic lustre and cream-coloured markings. 

 Head ordinary; front strongly aeneous or dark olive-green, 

 with scattered distinct punctures; clypeus cocked-hat-shaped, 

 cream-coloured, with the usual black dots rather large, and 

 two median longitudinal black bars, very broad and slightly 

 coalescing; labrum black; mandibles ordinary, basal half 

 cream-colour, apical half rufous ; face not very hairy ; a 

 distinct linear groove running down from middle ocellus ; an- 

 tennae dark, fiagellum light brown beneath ; lateral face-marks 

 triangular, rapidly narrowing from a broad base to a pjint on 



Ann. & Mag. N. Hist. Ser. 7. Vol. iii. 3G 



