103 291 



The species is rather rare. On 17/V 21 I had the good luck to get a sample 



from a little outdrying pond near Hillerød, containing a maximum ol' this charming 



little creature, some of the specimens carried male eggs, and from them the male 



was hatched. 



Pedalion. 



The old order Scirtopoda originally contained only the genus Pedalion with 

 the two species P. minim Huds. and P. Fenniciim Lev. In 1899 (p. 142) I referred 

 Triarthra to the fam. Pedalionidœ and de Beauchamp (1909, p. 41) has adopted this 

 view. One of the most striking structures in Pedalion are the two stylate ciliated 

 appendages on the posterior dorsal surface, unique in Rotifera. As they are totally 

 ahsent in Triarthra it should really be regarded as rather hazardous to refer Triar- 

 thra to this family, but as these appendages are also totally absent in one of the 

 two known species of Pedalion P. Fennicnm Lev. they seem to have no particular 

 systematic value. 



Pedalion miruni Hudson. 



Male: Hudson-Gosse 1889 n, p. 133. 

 Tab. XIV, fig. 7—8. 



Hudson Gosse (1889 ii, p. 133, PI. XXX, fig. 1 h, 1 g). 



The male is the merest caricature of the adult female. The large shapely corona, with 

 its flowing curves has become a ciliated knob; the six limbs, with their fan-shaped phniies, 

 have been altered into three little stumps, with a bristle or two at the end of each; even the 

 huge ventral limb has vanished, and the whole creature has shrunk up to barely one-fiftb 

 of the length of the adult female. It swims verj' ditferentlj' from its mother; for it spins con- 

 stantly round its own length, like a joint on a spit, while at the same time moving forward. 

 Now and then it jerks its side limbs, and it uses them to free itself from its shell. There are 

 two longitudinal muscles for retracting the head and a pair of red eyes but I could discover 

 no other internal organs except the testis and penis. This latter I have seen protruded to a 

 length quite equal to that of half the animal. Size: female il^ inch, male rAa- 



Description: The male is remarkably broad, almost globular with the forepart 

 rather sharply removed from the other part of the body; directly backwards protrudes 

 dorsally a thick humpback-like protuberance; laterally two others are found; these 

 protuberances differ in form in the different specimens and most probably in the 

 same specimen; they may be rather broad, faintly acute, very broad at base with a 

 sharply defined wing-like outer part; they end in a bunch of about five very short 

 bristles. Seen from above, the body is rounded behind. The wheel-organ consists 

 only of a ciliated disc, the marginal cilia of which are somewhat longer than those 

 in the middle of the disc. Of internal organs I have only been able to observe a 

 large brain with two curved red pigment spots, each with a lens and a very large 

 globular testis, containing comparatively few spermatozoa of both sorts. There are 

 no prostata glands. The penis is remarkably long, almost half the length of the body, 

 traversed by a long canal, covered with cilia; at the apex a wreath of short cilia. 

 If the penis in this genus too, is really only the posterior part of the body, drawn 

 out when it is to be used as a pairing organ, or if it is a real organ, concealed in 



