50 PEOCEEDINGS OF THE NATIONAL, MUSEUM. vol.60. 



slender than the other, as long as but more slender than those of 

 penultimate cerarius, two setae and a few pores; fourth cerarius 

 similar to third; remainder of cerarii, so far as can be determined, 

 represented only by slender, almost hairlike setae, possibly occur- 

 ring in pairs, but the members of such pairs widely separated ; anal 

 lobes obsolete, their location indicated by an apical seta about as 

 long as the anal ring setae, by a chitinized thickening of slight 

 density surrounding the apical cerarius, and by a small, narrow, 

 diagonal ventral thickening; derm dorsally with an occasional tri- 

 angular pore, still less frequently with a long, slender, hairlike seta, 

 and still more rarely with small tubular ducts; anal ring com- 

 pound, with a double row of pores and six rather large setae ; poste- 

 rior dorsal ostioles distinct; ventral surface in abdominal region 

 with rather numerous circular multilocular disk pores and hairs 

 arranged in transverse rows. 



Intermediate stage — not known. 



Larva — (from embryonic specimens within body of adult only) 

 oval, antennae 6-segmented, terminal largest ; legs not determinable ; 

 with a pair of somewhat developed anal lobes bearing an apical seta, 

 and on the inner face, the only pair of cerarian spines that are plainly 

 developed, these relatively large, conical; anal ring with six setae, 

 dorsum with triangular pores and setae, venter with slender setae. 



Cotype.—Ciit. No. 24763, U.S.N.M. 



The status of the species formerly included in the genus Erium 

 has already been discussed. It is sufficient to repeat here that none 

 of them appears congeneric with the true type of the genus. 



The following generic diagnosis is based on the preceding de- 

 scription, 



GENERIC DIAGNOSIS OF ERIUM. 



Pseudococcine forms, having dorsal ostioles and triangular pores; 

 adult female oval, approaching globular, enclosed in a fluffy sac, an- 

 tennae 7-segmented, normal, legs normal, claw without denticle, definite 

 cerarii reduced to not more than four pairs, cerarian spines conical, 

 posterior pair underlaid by thickening, with slight ventral thicken- 

 ing, apical seta about as long as those of anal ring, derm with setae, 

 but no spines, derm with triangular pores, multilocular disk pores, 

 and short tubular ducts ; anal ring compound, with two rows of pores 

 and six setae; larva oval, antennae 6-segmented, derm with setae 

 and triangular pores, with only the apical pair of cerarian spines 

 developed, anal ring with six setae. 



This genus, as based on the type species, appears to offer no dis- 

 tinct characters to separate it from the genus Trionyinus Berg, as the 

 latter has recentl}^ been emended by Ferris,^^ although it certainly 



" Calif., Species Mealy Bugs. 1918, pp. 35, 66. 



