NORTH AMERICAN COLEOPTERA. 87 



Color characters have their utility in the separation of sjDecies of 

 Scymnus, but some care and no little experience is required in their 

 use. In guttulatus the elytra may become almost entirely yellow, 

 while in nehuloms the small black spots may be so numerous and 

 large that the elytra appear almost entirely black. The legs vary 

 in color. As a general rule the species of the first two groups have 

 pale legs. In other species two colors exist — piceous and red. The 

 former color will vary to testaceous, while the latter may become 

 dark brown. It seems to me that too strict an insistance on the color 

 of the legs as of specific value is not advisable from the known ten- 

 dency to variation. 



From the characters given in the preceding remarks and the com- 

 ments upon them it is evident that primary groups based on the form 

 of the metacoxal line afford the most natural arrangement of the 

 species. 



Metacoxal line incomplete. 



Metacoxal line joining the first ventral suture Group A. 



Metacoxal line parallel with the first suture Group B 



Metacoxal line recurved at end Group C. 



Metacoxal line forming an entire arc beginning at tlie inner border of the coxal 

 cavity, varying in the degree of its curve, ending at or near the front angle 

 of the first segment Group D. 



Group A. 



In this group the metacoxal line passes in an oblique curve from 

 the inner edge of the posterior coxal cavity and joins the suture, 

 becoming evanescent. The species are all of small size, the elytra 

 ^ in the majoi'ity being ornate with spots or bands. The 

 prosternum is without elevated lines, or at most exhibits 

 very faint traces of them. The metacoxal arc forms a 

 very open curve joining the met-episternal suture near its middle. 

 The abdomen has six distinct segments in both sexes. 

 The species may be separated as follows : 



Elytra piceous, variably ornate o. 



Elytra yellowish testaceous 7 



2.— A post basal, slightly oblique yellow baud on each elytron balteatiis. 



Elytra with one or two spots on each ;j. 



Elytra narrowly tipped with yellow 6 



3.— One spot on each elytron, slightly in front of middle bigeiiiineu!^ % . 



One spot on each elytron often joined to a large pale apical area. 



bigeninieus 9 . 



Two spots on each elytron 4 



TRANS. AM. ENT. SOC. XXII. APRIL, 1895 



