\( i( 11 \ \ I I I 1 1 i;( )\s. iiov . sp. ( I'l.iic ."), li^-. (i. 9 ) 



Aiilfiior wiiin.s l)l)icUi.sli, ordiii.iry linrs iiitiTniiilcd, i);iU'; ii hrojul fostal 

 (lull rrcMin coldri'd hiiiid; ordin.iry spots snh-olisoiclc. 'l"r;itisv<Tsc iinlcrior 

 line undid.'dc, iiidisi iiu'l ; orbicul.i r spol \v;inliMa, icMil'iiiin irrcunl.ir, (hii-k 

 iTram , c'i>l<>r; traiisvci-sc poslcrinf line \cry .s||j^lill\ hcnl ;il llic disc, f'ui- 

 lowrd l>\' a scries of siiniiarlv cnlorcd sjimIs oh llic xi'iiis, wliicli l.illcr ,irc 

 darker shaded in Ihc Ici'iniii.i! nii.icc; Mili-lcrmin.d linr iindnl.i Ic, cunl inucd, 

 broadly marked al eosia; Ifiiiucs soinewhal ))aler Mian liie \\ iiiji'. I iider 

 surface wliitisli, witli a iijackisli suli-tcriiiina! sliadc, broadest at costa. 

 l'osteri(»r wiiiirs wliitisli, iiiiiiiaciilafe, with pale brownish scales aloiifx the 

 \eins; fringes whitish. I'ndcr surface whitish, s])rinkle(l with ])alc brownish 

 along file cosfa and at costal anjilc. C'oilai- concoloroiis with tiie costal 

 band of anterior wings, bnf with a deepei- lird al Ihc cciilcr; licad blackish, 

 ]ialer on the front: palpi blackish, terniiiial join! pale; Ihorax and Icgidae 

 blackish; abdomen eineroiis above, jialcr iindcriiealh ; Icus ciiierous, tarsi 

 paler. V.\p. $ L3.5 inch. 



Habitat.— Colorado Ter., Mr. .1. liidings. (Coll. Ent. Soc. Phil.) 

 With .\iicliiii plertii Linn, and X. arhrnfiasfer Gnenee belonging to 

 Hoi-sdiival's genus Chersotis (Ochropleiira IIui)n.). It is ;i more robust 

 and darker colored s]iecies than these, and with them cannot l)e generically 

 sejiaratcd from the other sjiecies of the genus Xoctiia. 



Tvi'E Locality: Colorado. 



Number and Sex of* Types: 1 9 



Types ix: Am. Ent. Soc, Pliila. 



Specoiens Exajiixed: Total, 20; from, Fort Wingate, X. Mex.; 

 Glenwood Spring.s, Colo.; Eureka, Deer Creek, Stockton, Utah; So. Utah; 

 Keno, Nev.; Truckee, Calif.; and Colo., (Bruce) ex. Coll. Jacob Doll. One 

 specimen, compared with type. Eureka, Utah. 



Gexetalic Mouxts: 1, Colo., (Bruce). 



GROUP TRIGONA 



This group contain.s two species: tricjona, Sm., and numbo, Sm. 



It is readily distinguished from all other groups bj^ the short, stubby 

 wingform, (trigonate wingform of Smith). In addition the thorax is with- 

 out a di.stinct crest; altlio in some specimens the thoracic vestiture is so 

 arranged that a trace of a keel-like crest is barely visible. The antennae 

 of the males have a dense scaling to the joints; and the cilia are as long 

 or longer than the width of the shaft, projecting directly outward in block- 

 like pattern. This combination, coupled with the absence of the cilia from 

 the ends of the antennal segments, causes a subserrate appearance to the 

 antennae. This is quite a conspicuous feature in trigona. In sambo the 

 antennae of the males is of this pattern for only about one-half of the 

 length of the .shaft, the terminal half being more of the type of placickt. 

 The wings of sambo are slightly less trigonate than those of trigona. 



The Trigona Group appears to be a connecting link between the Placida 

 Group and the Subgenus Abagrotis. 



Superficial Key to the Trigona Group 



I- — ^^ ingform short, stubby, broadly trigonate ; antennae of 

 male with cilia arranged in block-like pattern on the 

 segTnents, causing a subserrate appearance due to their 

 absence between the segments trigona 



86 



