DISCUSSION OF GENERA AND SPECIES 



49 



the presence of numerous ducts near the margins of the last abdominal 

 segment anterior to the pygidium. The presence of these ducts will serve 

 to separate this from the very similar A. densiflorce Bremner. 



Fig. 25. Aspidiotus arctostaphyli Ckll. and Rob. : pygidium of specimen from near 

 Redding, Calif. 



Aspidiotus coniferarum Ckll. 



Fig. 26. 



Abundant on the bark of Libocedrus decurrens, on the campus of 

 Stanford University. It is probably introduced. It has previously been 



Fig. 26. Aspidiotus coniferarum Ckll. : pygidium of specimen from Libocedrus 

 decurrens on the Santa Cruz Peninsula. 



