122 THE COCCIDAE 



cerari, thoracic cerari, and abdominal cerari. There may be twc 

 rows of cerari on the dorsal aspect between the lateral cerari. 

 the dorsal cerari, and if a single dorsal row should be present, they 

 could be known as the mesal cerari. The setae of the cerari are 

 not always short and conical, but may be long and slender like 

 the other setae in certain species. There are often ordinary setae 

 associated with the cerari, named the auxiliary setae by Ferris to 

 distinguish them from the conical setae of the cerari, the ceraran 

 setae. The ordinary setae of the dorsal aspect are known as the 

 dorsal setae. The number of ceraran setae varies from two to 

 twenty, the largest number so far observed. If there is a vari- 

 ation in number between the various cerari, there is likely to be a 

 larger number in the first six cerari or in the anal cerari. The 

 cerari are sometimes obscure in the adult female, probably due to 

 the swelling of the body by the eggs, but are generally very dis- 

 tinct in the half grown nymphs. In certain genera, as Antonia, 

 the cerari are wanting ; are represented by only a few in others, as 

 Trionymus, where only the anal cerari are present in some species, 

 while others may have four pairs; or there may be a considerable 

 number of pairs as in many species of Pseudococcus. The number 

 varies from a single pair to as many as twenty-four pairs in 

 Macrocerococcus as figured by Leonardi. 



Marchal and Ferris have described some minute cylinders 

 which are connected with the external cuticle of the body-wall. 

 Each is represented as having one side of the distal end continued 

 as a much smaller cylinder. These cuticular cylinders are con- 

 sidered as the outlets of wax cells, which are circular in outline. 

 The number in destructor seems to be variable. I have found 

 them more often along the margin of the body near the anal lobes. 

 Some species seem to show them in considerable number. They 

 are regarded as ceratubae. 



The ventral aspect of the abdomen of the female bears the 

 numerous cerores from which the cottony threads of wax in which 

 the female conceals herself and her eggs. These cerores are 

 peculiar to the adult female, are typical in form, and like the 

 genacerores do not appear until after the last molt. 



Berlese has called attention to the presence of four peculiar 

 structures located on the dorsal aspect which he designates as the 

 foveola labiate. There is two of them on the head and two in the 

 coria between the sixth and seventh abdominal segments. These 



