376 APHIDS OF THE ROCKY MOUNTAIN REGION 
segmented antennae occur among the cotypes; so unless a mixture of species 
exists in the cotypes, this removes the distinguishing characters between the 
genera of Tullgrenia and Trifidaphis. Essig states in correspondence that a 
probable mixture of species exists in the cotypes but proof that they are not 
variations is lacking. 
Species Not Included in Key ; 
Not included on account of uncertainty of characters, both specific and 
generic, due to lack of alate specimens and present unavailability of typic 
material and specimens used by Cockerell. 
Forda interjecti Cockerell 
Forda interjecti Cockerell (W. P.), 1903:217. 
Apterous Vivipara. Bright yellow; cauda brown. Body oval or ovate with sutures rather 
distinct; antennal I .045, II .06, III .12, IV .06, V .114+.024. Hairs not evident on body and 
antenna; cauda hairy. 
Recorded in ants’ nest. New Mexico: Las Vegas and Las Valles. Apterous 
viviparae March 22 and 24 and Oct. 11. (Data for above description obtained 
from original description.) This species resembles F. olivacea, especially in 
color, but differs in measurements of antennal segments. 
Geoica lucifuga (Zehntner) 
Tetraneura lucifuga Zehntner, 1897:555. 
Pemphigus lucifugus, Cockerell, 1904 :262. 
Geoica lucifuga, Mordvilko, 1935:214. 
Recorded by T. D. A. Cockerell from New Mexico without description, host 
plant, date or locality. 
(Not described here on account of unavailability of collected specimens 
from region.) 
Tychea crassa Cockerell* 
Tychea crassa Cockerell, (W. P.), 1903:218. 
Apterous Vivipara. Brownish. Eye very prominent, on tubercle. Hairs on body Sparse, 
appendages hairy. Body length 3; antennal I .075, II .117, III .132, IV .069, V .114+-.30. 
Collections. In ants’ nests. New Mexico: Old Pecos (near Rowe). Apterae - 
April 2. 
Data for above description obtained from original description. 
Tychea pallidula Cockerell* 
Tychea pallidula Cockerell, (W. P.), 1903:217. 
Similar to P. lasii, differing as follows: Light yellow body, small size, eye 
on tubercles, antennal segments as follows: I .03, II .06, III .056, IV .03, V .09-+- 
.018. These individuals were evidently oviparae as they were described as con- 
taining eggs. 
Collections. In ants’ nest. New Mexico: Beulah. Apterae March 28 “and 
several times afterwards.” 
Data for description were taken from original description. 
Subfamily Hormaphinae Gillette and Palmer 
Hormaphidinae Baker, 1920a:81. 
Hormaphinae Gillette and Palmer, 1934:241. 
Characters. Frontal tubercles lacking. Thoracic lobes not evident. Cornicle 
mere ring or absent. Scalelike or aleyrodiform generations often developed. 
Sexuales small and apterous, with rostrum; ovipara laying several eggs. Living 
in galls or exposed. 
*Genus as determined by Mrs. Cockerell. Tychea Koch is a synonym of Pemphigus 
Hartig (Baker, 1920a:71). Tychea as used by Passerini is a synonym of Geoica Hart 
(Baker) (op. cit.). Determination as to which of these genera these species belong is 
impossible without more characters not only of apterae (the specimens of which are 
at present unavailable) but of alatae, which latter were not taken. 
