496 Pomona College Journal of Entomology 



to C. W. Mally, Psylla quadrilineata is identical with Aph. polygoni, and therefore 

 is undoubtedly another synonym of Aph. callhae. 



The species has apparently a world-wide distribution and consequently is sub- 

 ject to more or less minor variation. The color varies from light to dark brown, 

 sometimes almost unicolored, and often somewhat variegated. The notal stripes, 

 for which Fitch named his quadrilineata, are usually very prominent, sometimes 

 scarcely diflferentiated from tlie ground color when this is quite light, and some- 

 times the stripes are almost wanting on the darkest notum ; the wings are usually 

 subhyaline, fumose, especially in the apical half, less so in basal half; often they 

 are fulvous-fumate throughout, by transmitted light darker apically; the vena- 

 tion is always conspicuous, though some of the venational characters are variable. 



The distribution in the United States as represented in the collections at hand 

 is as follows: In the C. F. Baker collections from Colorado, Arizona, California, 

 Oregon, Washington, Idaho, Louisiana, Illinois, Massachusetts ; Colorado (E. S. 

 Tucker), Texas (E. S. Tucker) ; Canada (C. F. Baker) ; ISIexico (C. F. Baker) ; 

 Havana, Cuba (C. F. Baker). 



From a single female from Aaken, Germany, determined by Dr. F. Low as 

 Aphalara exilts W. & !M., it seems that it is very probable that this species is 

 synonymical witli Aph. calthae L. 



Aphalara calthae maculipennis Low 



(Syn. Aphalara cxilis rinnicis Malh') 



(Figure 157, R; 158, N; 159, L; 160, T) 



This variety was described by F. Low in 1886. As the name indicates, the 

 chief difference lies in the maculation of the wing in the apical portion. This 

 is probably onh' an intensification of the apical fumose condition in the species. 

 About the only prominent structural difference is in the labrum, which in the 

 variety is relatively sliort and lying close to the face, not elongate and truncate 

 and extending downward as in the species. The abdomen is often relatively stouter 

 in the female than it is in the species. The notal stripes are less conspicuous. 

 The characters of the labrum and the abdomen were not given by Low, but are 

 quite probably true of liis types. Whether or not these characters are of specific 

 value will have to be determined by further study; for the present this will re- 

 main as a variety of the species. The size of the insect varies quite widely, as it 

 does also in the species. 



Redcscribed from specimens in tlie C. F. Baker collections from Colorado, Ari- 

 zona, Oregon, Washington, Illinois, Texas (E. S. Tucker). From Mally's de- 

 scription of his variety of Aph. exilis W. & M., it seems beyond a reasonable doubt 

 that it is synonymical with Low's variety of calthae. 



Aphalara artemisiae Forster 



(Figure 157, O) 



(Syn. Psylla malachitica Dahlbaum) 



Length of body 2.0 mm.; length of forewing 2.6 mm.; greatest width 1.0 mm.; 



width of vertex between eyes .18 mm. ; with eyes .82 mm. ; length down center 



.36 mm. General color greenish white to greenish yellow througiiout. Body 



quite variable in size. 



