58 THE CANADIAN ENTOMOLOGIST 



The most objectionable feature of the book is the great number of new 

 genera that have been proposed in the subfamily Diaspidinae, practically all of 

 which are based upon species that in all probability the author has never seen. 

 That many new genera are needed in this group is undeniable, yet before the 

 wholesale naming of them is undertaken there should first be a careful review 

 of the types of the existing genera, and the whole work should be based upon 

 an examination of specimens. The naming of new genera upon the basis of 

 printed descriptions alone is not likely even under the most favorable conditions 

 to be especially helpful. When done under the conditions prevailing in the 

 literature of this group and in such wholesale fashion as attempted by Mac- 

 Gillivray it is little short of disastrous. The peculiar results that can thus be 

 obtained will be discussed in connection with this subfamily. 



It is not probable that anything approaching unanimity of opinion con- 

 cerning the general classification of the Coccidae will be arrived at for many 

 years to come. There remain too many questions, such for instance as the 

 taxonomic value of the various types of ducts and pores, that are still to be 

 investigated. Doubtless, too, the discovery of new forms will profoundly 

 change some of the present conceptions. As it is, even with the specimens 

 before one, there are many points concerning which the cautious student will 

 hesitate to express an opinion. Yet there are some things that are fairly clear 

 and concerning which an opinion may be hazarded. 



My own personal preference would be to regard the Coccida? as a super- 

 family in the belief that a more expressive classification can thereby be ob- 

 tained. However, this is a minor point. What is really desirable is to obtain 

 a division into groups that will approximate a natural arrangement and that 

 are somewhere near equal rank. This I consider that MacGillivray's proposed 

 seventeen subfamilies do not do. I am unable to see that his arrangement is 

 any special improvement over the classifications that have preceded it. 



It is my contention that MacGillivray's six subfamilies, Monophlebinse, 

 Kuwaniinae, Xylococcinae, Margarodinae, Callapappinae and Ortheziinae taken 

 together constitute a group that is equivalent in rank to, for instance, the sub- 

 family Diaspidinae. In working over the Coccidae I have been impressed with 

 the feeling that the group is at once extraordinarily conservative and extra- 

 ordinarily plastic, and in no place is this paradoxical condition shown to better 

 advantage than in the six groups mentioned above. There is throughout this 

 group of species a persistent adherence to a certain fairly definite general type, 

 coupled at the same time with aberrations of the most remarkable characters. 

 It is the adherence to this general type and not the aberrations to which I am 

 inclined to accord the most weight. 



This group as a whole is characterized by the presence of abdominal 

 spiracles. It is true that in many of the species they have not been recorded, 

 yet there is good reason to believe that this is due simply to deficient observa- 

 tion. In but two genera, Nipponorthezia and Newsteadia, each with a single 

 species, do they appear positively to be lacking. 



MacGillivray in his key to the subfamilies (pp. 58, 59) separates the 

 Ortheziinffi from the other groups named above on the basis of the presence of 

 an anal ring and anal ring setae. As a matter of fact the anal ring is some- 

 times developed in the Monophlebinae, being well developed but simple in 



