16 (dr. a. c. oudemans). new list of dutch ACAEI, II. 



The dorsal side 'is protected by a shield (Fig. 12) over which 

 are spread a few very fine liairs. The soft skin round the shield 

 bears little hairs of the same kind. 



The ventral side (Fig. 13) shows a sternal shield, exactly re- 

 sembHng that of Lipon^ssus albatus (G. L. Koch). There is a genital 

 shield , the posterior margins of which are rounded and distinct , the 

 anterior, however, are indistinct. Between the sternal and genital 

 shields the skin shows the usual folded appearance. The anal 

 shield is remoted fi-om the genital one by a space of its own length. 

 The female's peritrenia reaches far more forward than the male's; 

 it goes beyond the inplantation of the first leg. The remaining of 

 the ventral side is soft and bears numerous fine hairs. 



The chelae (Fig. 44) have no appendage. The movable finger is 

 yellowish ; the other quite transparent. 



All the legs are normal. The fourth pair has not such strong 

 bristles as in the male. 



11. Key to ths species of Liponyssus Klii. 



c? with 1, Î with 2 dorsal shields .L. inusculi (G. L. Koch). 



S and ? with 1 doi'sal shield . . .2 

 1 Î sternal shield present ... .3 



\ No sternal shield more 8 



I Î sternal shield trapezoidal . . .4 

 / î sternal shield linear 7 



4. 



end of anal shield cribrated . . .5 

 end of anal shield smooth ... .6 

 J. ^ c? with spur on femur 3 . . . .L. lacertarum (Gont.) 



\ <? without spur L saurarum Oudms. 



P j c? with broom of bristles around anus. L. corethroproctus Oudms. 

 I i without broom L. albatus (G L. Koch). 



7. only one species L sylv'arum (G. et F.) 



8. only one species . L uncinatus (Gan.) 



N B. A better «key» will, however, be found in the Tijdsckr. 

 der Ned. Dier Jc. Vereen., ser. 2, v 7, p. 68 — 69 {Notes on Acari, 

 Hid Series), which has appeared Nov. 30, 1901. 



