OF THE FAMILY COCCIDAE 37 



to be homologous to the basal rod (bra) found in other Coccoidea (see Theron, 1958, 

 1962), but was overlooked by Theron (1958) in P. pomeranicum. According to 

 Theron the basal rod may incorporate the basal plate. Parameres are absent. 



Posteriorly the basal rod is connected to the base of the aedeagus (aed), which is 

 accommodated in a slit in the ventral wall of the penial sheath. The aedeagus 

 consists of a straight tube, which does not narrow appreciably towards the apex. 

 It ends bluntly before reaching the apex of the penial sheath. The ductus 

 cjaculatorius can be seen to run along the ventral wall of the penial sheath, but the 

 position of the gonopore is impossible to observe in mounted specimens. The 

 aedeagus appears to contain an eversible endophallus, as is indicated by occasional 

 specimens in which the everted condition has been observed. The genitalia with 

 everted aedeagus, but considered to represent the normal condition, were illustrated 

 by Sulc (1932). The relative length of the penial sheath, aedeagus and basal rod 

 show considerable variation within the family. Silvestri (1919a, 1919b, 1920) and 

 Jancke (1955) correctly illustrated and interpreted the aedeagus, while the illus- 

 trations given by Leonardi (1920) and Theron (1958) are inaccurate in some details ; 

 Putnam (1879), Dvirr (1954) and Husseiny & Madsen (1962) called the entire 9th 

 segment either a penis or aedeagus. 



In well stained specimens of some species (e.g. the COCCUS group ; Text-figs. 

 31-43) a small gth tergite (atg) can be seen in the membrane anterior to the anus, 

 but the 10th and nth tergites described by Sulc (1932) were not observed. 



Dermal structures. A number of small setae (gts), which are possibly tactile 

 sensilla, are scattered over the genital segment. Distally the setae become con- 

 siderably smaller and at the apex only small, circular discs can be discerned ; the 

 latter may be campaniform sensilla. 



DESCRIPTION OF THE SPECIES 



In the descriptions of the individual species considerable detail has been included 

 and they may well appear to be unduly long and repetitive. However, detailed 

 descriptions are considered necessary since the taxonomic significance of the 

 characters has, as yet, not been properly evaluated. 



For the sake of brevity the usual telegraphic style of describing species has been 

 adopted and the following abbreviations are used : h.s. = hair-like seta(e), f.s. = 

 fleshy seta(e) ; the figures in brackets signify averages. 



The EULECANIUM Group 

 EULECANIUM 



Eulecanium tiliae (Linnaeus) 



(Text-figs. 2 and 3) 



Living specimens reddish, with sclerotized areas dark brown and the appendages light yellow, 

 wings with a purplish tinge between anterior margin and first wing vein ; very long and 

 moderately robust, with comparatively short antennae and legs which carry many setae. 



