602 



IVAR TRAGArDH 



of the lamellae. The pseudostigmatic organs are fairly long; curved obliquely 

 upwards and backwards at an almost right angle. The peduncle is very thin, 

 the head very slightly thickened, spindle-shaped, about half as long as the 

 peduncle, pointed and with rough surface. 



Mouthparts. Oudemans is, as far as I know, the first one who has 

 called attention to the peculiar shape of the hypostome, which is to be found 

 in some of the Galumninae (1919, p. 36). In most of the Oribatei the floor 

 of the camerostomum is formed by a large plate, the so-called hypostome, to 

 which the maxillae are joined. Sometimes, as in the Phthiracarinae, the hypo- 

 stome is rather small, the greater part of the floor being formed by the max- 



Figs. 104 — 108. Gabtmna pacifica n. sp. 



104. Left half of propodosoma. 105. Pseudostigmatic organ. 106. Hypostoma. 17. Palp. 



108. Area porosa mesonotica. 



illse. In the Galumninae, as OUDEMANS has pointed out, in some species the 

 hypostome has developed to such an extent, that it occupies the whole space, 

 the maxillae having as a consequence been pushed forwards so that they are 

 inserted on the dorsal side of the hypostome. This is the case in G. 

 pacifica, where they are barely seen along the edges of the hypostome 

 (fig. 106). 



Palps (fig. 107) with very short basal joint, the 2nd joint is very large 

 and flattened from both sides, its length being equal to twice its width (on 

 lateral view); along the ventral margin there is a narrow, thin, browncoloured 

 blade running forwards as far as to the ventral bristle, which is straight and 

 points downwards; in front of it there is another narrower blade; on the ex- 

 ternal side almost in the middle of the joint there is another hair, curved in 

 an even curve forwards and upwards. 



