10 
THE VOYAGE OF H.M.S. CHALLENGER. 
The male is 13 to 16 mm. in length; the tail end occupies of the total length; 
the two cirri are of equal breadth, and measure 0 ’ 7'2 and 0'86 mm. in length ; the shorter 
has a bow-shaped curvature in the middle, and the longer is sabre-shaped ; in front 
of the cloaca there are on each side four very small, scarcely perceptible papillae. The 
female measures 29 to 31 mm. ; the tail end occupies only T 2 V 1 °f the total length ; the 
vulva lies very far forward, only 0'6 mm. distant from the head end. The ova are ellip- 
tical and very thick shelled; the shell is 0'0066 mm. in thickness; the ova are 0 - 049 
mm. in length and 0'031 mm. in breadth. 
This Filaria was found by R. von Willemoes Suhm, v T ho died on the Challenger 
Expedition. He has referred to it in the following lines d — “ Under the skin and on 
several positions in the abdominal cavity I found free Filarise , such as not unfrequently 
occur in our crow-like birds. There were no other Helminths in the intestine. This is 
probably the first time that any one has examined fresh Birds of Paradise in search for 
Helminths, and the case is on that account worth noting, since the beautiful creature is 
always mentioned in the first rank of birds, although it is in reality nothing more than 
‘ a crow developed by sexual selection.’ ” 
Five species of Filaria are known in which the mouth exhibits a chitinous armature 
similar to that of the above form. 
Filaria tricuspis, Fedtschenko, 2 from Corvus cornix, which is very similar to the 
above species, but has larger cirri, which measure 1'6 and 1*2 mm. in length, while the 
chitinous plates on the head are smaller, attaining a length of only 012 mm. The total 
length is, however, much greater, for the female is 150 mm. in length. Filaria ecaudata, 
Oerley, 3 from Lamprotornis aeneus, is very probably identical with Filaria tricuspis, 
Filaria obtusa, Rudolphi 4 (non Schneider), from Hirundo rustica, Hirundo urbica, and 
Hirundo riparia has its breadth and length in the proportion of 1:80, and the shorter 
spicule is twice as broad as the longer. 
Filaria pungens, Schneider, 5 has numerous large papillae on the tail end of the male, 
and was found in Turdus cyaneus. 
The unnamed Filaria found by Parona 6 in Buceros nasutus was a female, so that 
comparison is impossible. 
It is remarkable that these species, which resemble one another so closely, were all 
found in Birds. 
1 Challenger Briefe von R. v. Willemoes Suhm, Leipzig, 1877, pp. 127, 128 ; Zeitschr. f. iviss. Zool., Bd. xxvi. 
p. lxii., 1875. 
2 Soc. Nat. Hist. Moscow, x. pp. 10-11. Von Linstow, Archiv f. Naturgesch., Jahrg. xlix. Bd. i., 1883, p. 285, pL 
vii. fig. 16. 
3 Oerley, Report on the Nematodes in the possession of the British Museum, Ann. and Mag. Nat. Hist., ser. 5, 
vol. ix. pp. 312, 313, pi. x. figs. 1 a-d, 1882. 
4 Dujardin, Hist. Nat. des Helminthes, pp. 53-54, pi. iii. fig. J, 1-2. 
6 Monographie der Nematoden, pp. 92, 93, pi. vi. fig. 2. 
0 Di alcuni elminti raccolti nel Sudan orientale, Genova, 1885, pp. 433, 434, pi. vii. fig. 14 . 
