SUBORDER MALLOPHAGA. 199 
THE PIGEON LIPEURUS. 
(Lipeurus baculus Nitzsch.) 
This is another of the species that was given a name and figure in 
the work by Redi more than two hundred years ago. It was also 
described briefly by Linnzus under the name of Pediculus columbe; but 
since the description by Nitzsch in 1818, under the name of Lipeurus 
baculus, this has been the accepted name, and has been used by nearly 
all writers since that time.' It is not strange that it attracted the 
attention of early naturalists, as it occurs in wonderful abundance on 
almost every pigeon that may be examined, and its striking appear- 
ance, due to the extreme slenderness of the body, would at once catch 
the eye of the observer. 
It is about 2 mm. in length, the body very slender; the head and 
thorax are of a bright reddish-brown color, while the abdomen is 
rather dusky, with a series of patches of a brown color corresponding 
with the segments of the abdomen. 
So far as known, this species is confined to pigeons, and there seems 
no danger of their being transmitted to other fowls 
with which they may associate. 
Piaget states that he has found the females astray 
upon a Sula alba, upon a Totanus glottis, and upon a 
Charadrius minor, only in the last case the appendages 
of the clypeus wanting; the last segment had the 
lobes more acute and the dimensions were less. 
Denny described, under the name of Nirmus clavi- 
formis, what appears to be the young of this species, 
though he gives measurements for males and females, 
which would seem to indicate that he was able to see 
the sexual organs. In all the specimens we have 
4 : : ee Fic. 121.— Lipeurus 
examined that agree with his figure and description of She ER Ste 
this form we have been unable to discover the genital (author's illustra. 
organs, which makes it appear that they are immature,  “°"” 
and they are in all cases associated with the laculus, with which they 
seem to agree in all structural characters. The body is shorter, the 
markings less distinct, and the rudiment of a trabecula is more promi- 
nent than in the adults. 
It seems best, therefore, at least till well-marked males and females 
can be found, to consider these as immature baculus. 
Piaget does not discuss this matter, but in his index to ‘Les Pédie- 
ulines” he gives NV. claviformis as a synonym of L. baculus. 
1Giebel names and describes two species, bacillus and baculus, referring both to 
Nitzsch, and placing under bacillus the form which all other authors refer to baculus, 
and referring to baculus a form not separated by other authors, but which he de- 
scribes as different from the other form. It seems undesirable to add names without 
a more decided difference in form, and we agree with Piaget in uniting both under 
the old name. 
