1911] 



Specific Characters in Pseudococcus 



311 



TABLE 4. Pseudococcus crawii Coq. 



Also only the larger individuals were studied because of the 

 danger of including those in the nymphal stage. Each species 

 was collected from the same or neighboring host plants and 

 were apparently under similar conditions, so that size cannot 

 be taken as a specific character of any great importance. These 

 measurements were taken from mounts. If unmounted spec- 

 imens were used, the variation would probably be still greater, 

 as then a second factor, namely, the amount of secretion pres- 

 ent, would enter. Because of the great variation in size of the 

 different individuals in a species the size of a specimen can be 

 of but little if any value in specific determination. 



2. Shape. — In descriptions the shape of the body is vari- 

 ously given as elongate-ovate, rounded-oval, convex, tapering 

 at ends, elongate, etc., words which are nearly synonymous. 

 A few species are stated to be considerably out of the ordinary 



