CLASSIFICATION ' OF ACAEINA. 27 



the text of the classification ; there the descriptions of 

 the various orders, sub-orders, and families are set out 

 in ample detail, but this makes it so long that I should 

 hardly be justified in translating the whole of it here ; 

 and it is, I think, scarcely fair to summarise another 

 author's classification. I therefore confine myself to 

 giving the tabular review at the end, and fully trans- 

 lating the portion of the paper which defines the groups 

 leading up to the Tyroglyphidas which are the imme- 

 diate subject of this work, viz. : 



OEDEE I Astigmata. Without tracheae, and there- 

 fore without stigmata, not only in the immature but 

 also in the adult stage. Palpi of three or four joints, 

 simple, having the first joint fixed. Mandibles chelate 

 or styliform. Without eyes. Cuticle slightly chitinized. 

 Legs of three to five joints. Organization usually very 

 imperfect. 



SUB-OEDEE I Vermiformia, Body elongated, ver- 

 miform. Abdomen with superficial circular strise. 

 Adults with two or four pairs of legs. Mandibles sty- 

 liform. Without genital or copulative suckers. Para- 

 sitic creatures ; either animal or vegetable feeders. 



SUB-OEDEE II Sarcoptina. Body rounded, not ver- 

 miform. Abdomen not striated. Adults with four 

 pairs of legs. Palpi of three joints usually simple and 

 filiform. Mandibles chelate. Legs of five joints. 

 Larva hexapod. Metamorphoses, at least in some 

 species, binymphal, sometimes complicated by the 

 appearance of a Hypopial form. 



The definition of the family Tyroglyphidse will come 

 more properly into the next chapter. 



The table is as follows : 



