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



rniis to M. tlielypodii, Ckll., to wiiicli it is closely allied^ 

 differing conspicuously, however, iu the colour of the pubes- 

 cence. If placed with the species having the hair on hind 

 basitarsus fu.scous, it runs to il/. hlakei^ Cklh, which differs 

 greatly in the colour of the abdominal pubescence, and is not 

 especially related. The eyes of Mtei are light green. 



Hah. Fueblo, Colorado, Aug. 17, 1907 [G. M. Bite). 



The Mtlissodes of the martin{-thelyj)odii series do not visit 

 Compositse (so far as our records show) ; those of the hlahei- 

 mizece series are visitors of Corapositfe. 



Tetralonia clirysohotri/m, sp. n. 



? . — Length about 15 mm. ; anterior wing 9 mm. 



Abdomen with very conspicuous entire pale bands on 

 segments 3 and 4 ; on 1 and 2 the hair is mouse-colour, but 

 the band on 2 is whitish posteriorly at (be sides; on the fifth 

 segment the broad a[)ical band has the middle third dark 

 reddish fuscous and the lateral thirds brownish white; hind 

 basitarsi with the hair on inner side bright ferruo-inous and 

 on tlie outer golden ; small joints of tarsi ferruginous. 



In my table in I'rans. Amer. Ent. Soc. 1906, this runs to 

 7'. speciosa or cordleyi, the hind spur not being at all hooked. 

 Compared with speciosa it is considerably smaller, with much 

 darker tegula^, and the bands on abdominal segments 2 and 3 

 practically straight, not undulating laterally as in speciosa. 

 Compared with T. cordJeyi it is narrower, and the hair 

 on the fifth abdominal segment is quite differently coloured. 

 Compared with T.frater aragaUi it is easily known by the 

 narrower and much whiter bands on segments 3 and 4. 

 These bands, however, are yellowish white, not greyish as in 

 T. anna;. 



^ . — Hair of thorax above yellowish white or very pale 

 yellow ; clypeus, labrum, and small supraclypeal mark pale 

 lemon-yellow; yellow of clypeus squarely notched at sides; 

 mandibles with a veiy minute light basal spot ; second abdo- 

 minal segment covered with pale hair, except the apical 

 margin, wlieie it is black ; tarsi ferruginous, normal, hind 

 basitarsus a little longer than the other joints together. 



In my tables runs to T.frater (Cressou), having the meso- 

 thorax dull and the hind spur normal. Compared \\\\.\\ f rater 

 (a Cressonian cotype) it differs by the longer (much longer 

 than wide) third antennal joint, the lighter yellow of tlie 

 clypeus, the broader face, and the better-defined (though 

 narrow) bands on segments 3 to 5. The fourth and fifth 



