THE GENUS LEBERTIA. 509 



in the imago, the intervals being twice as great as in the latter. 

 Any fine pores which may be present are extremely difficult to 

 detect. The capitulum and the epimera resemble those of the 

 adult form. 



The palpi are about 0'22 mm. in length. The first segment is 

 devoid of bristles. The second segment has one or two bristles 

 distal and one about the middle of the extensor surface. The 

 third segment has two rather long distal bristles, one at the 

 extensor surface and the other about midway on the inner 

 surface. The fourth segment has the usual two pores on the 

 flexor surface. 



The legs are about 0*40 mm. long for the first pair; 0*45 mm. 

 for the second pair ; 0'52 mm. for the third pair, and 068 mm. 

 for the fourth pair. The terminal segments of the second, 

 third and fourth pairs are like those of the adult. Swimming 

 hairs are also wanting. 



The provisional genital area has four acetabula surrounded 

 by a chitinous ring, which is open towards the posterior and 

 anteriorly is attached to the ligulate muscle attachment plate. 



The larval stages are at present unknown. 



Lebertia stigmatifera Sig Thor. 

 (Sub-gen. Heocalebertia.) 



1900. Lebertia stigmatifera Sig Thor Nyt. Mag. for Naturvid., 



xxxviii. 275-276, pi. xi. figs. 7-9. 

 1907. Zool. Anz., xxxii. 150-157, figs. 87-90. 



Lebertia stigmatifera was taken by Mr. Deeley in Worcester- 

 shire. It is here recorded as an addition to the fauna of the 

 Britannic area, and is another link in the chain connecting the 

 Scandinavian and British faunas. It belongs to the smaller 

 species, a common size being about 0'7 mm., though extremes 

 of 0'58 mm. to 1*05 mm. have been recorded. 



The body is very nearly circular in outline, with the anterior 

 margin rather flattened. The ground colour of the body is 

 yellow, with large brown patches and the usual T-shaped yellow 

 outline on the dorsum. The skin is comparatively thin, and is 

 adorned with chitinous ridges, for the most part lying parallel to 

 one another. The skin is very indistinctly porose ; in the case 

 of the more heavily chitinised parts, the common large pores are 



