24 
IVAR TRÄGÅRDII, 
(Schwed. Südpolar-Exp. 
io. Bdella antarctica nov. spec. 
(PI. II, figs 9, 12 & 21.) 
Average length 0,82 mm. Average breadht o, 3 e mm. Length af rostrum o, 3 o mm. 
General shape like that of B. vulgaris (Herm.) K. Céphalothorax well demarcated 
from the abdomen, o, 3 mm. long, with 3 pairs of long hairs inserted in deep pores; 
one pair is situated not far from the anterior margin, the two others of which the 
ateral one is the longest, are situated on a level with the posterior pair of eyes. 
On the dorsal side of the abdomen are 4 rows of hairs and at the hind margin 
4 pairs. 
Ventral side. Coxæ I nearly contiguous in the middle, with 5 pairs of hairs, of 
which 3 near the antero-lateral margin and 2 near the postero-lateral angle; coxæ II 
with 6 pairs, coxæ III with 8 and coxæ IV with 3 pairs of hairs. 
Genital aperture oval, long, with 10 pairs of hairs. 
The legs. Trochanter I and II at the antero-lateral angle with a straight hair, 
somewhat longer than the others. Femur not very distinctly demarcated from telo- 
femur, especially in legs I and II. One long sense hair at the top of tibia I and IV 
and at the base of tarsus III and IV. Length of legs (excl. coxa and trochanter): 
I 0,48 mm, II 0,42 mm, III 0,52 mm, IV 0,62 mm. 
The mandibles very narrow, o,o 4 s mm by a length of 0,296 mm, the greatest 
width close to the base, from thence gradually narrowing with straight edges. Chela 
very short, edentate (PI. II, fig. 9). Near to the chela on the exterior side a small 
pore. Two hairs on the exterior side of the mandibles, situated much more forward 
than in B. decipiens [12, PI. II, fig. 3]; the posterior hair is situated very near to 
the middle and the anterior one half way between the posterior one and the tip 
(PL II, fig. 21). 
The palpi short, not exceeding the length of the rostrum; the third joint partly 
fused with the second one; on the exterior side is to be seen no trace of the fusion 
but on the interior side there is an oblique fold. The second (2 + 3) joint on the 
ventral side, near to the base, with two rather long, perpendicular, slightly curved 
hairs; on the exterior side, in the proximal half, three hairs; on the dorsal side, in 
the distal half, two hairs, and on the interior side in the middle, three hairs. Third 
joint, narrow, cylindrical, with two dorsal, one exterior, and one interior hair. 
Terminal joint triangular, with squared end, half as broad as long; two long 
terminal hairs inserted in large cup-shaped pores; on the dorsal side near the end 
one long hair, on the external side one, and on the internal side two small hairs. 
Rostrum with only 2 pairs of hairs. 
