SUBORDER MALLOPHAGA. 215 
species of pigeon lice, and it has not been found as yet on pigeons that é 
we have had an opportunity to examine. 
It does not appear to have been found on any other birds, but has 4 
been taken from the common domestic pigeon and also the turbot. 
THE SWAN LOUSE. 
(Colpocephalum minutum Rudow.) 
Rudow seems to have been the first to recognize this species, though 
its occurrence upon the swan (Cygnus musicus) makes it rather strange 
that it should have escaped observation so long. It 
is a very small species, as would be inferred from the 
name, and this may account in part for its not having 
been earlier noticed. , 
It has not been recorded from this country, but 
may be looked for upon our species of swans, as the 
lice infesting these birds are generally widely distrib- 
Tod) 
uted. | 
LOUSE OF THE GUINEA PIG. 
| (Gyropus gracilis Nitzsch.) 
> The guinea pig is perhaps a rather unimportant 
; factor among the domesticated animals, but it sup- 
ports its due quota of parasites nevertheless, and they 
require a brief mention, at least. They are quite in- 
teresting in structure, differing largely from any of 
the species considered hitherto. 
- The one to first receive notice, and probably the 
one here given, was referred to by Schrank under the 
name of Pediculus porcelli, 
but Nitzsch, in 1818, de- 5... 130 Garon 
scribed it as Gyropus gra- — gracitisenlarged 
cilis, a name which has ter Denny). 
been used by all subsequent writers. 
It is referred to generally by writers on the 
subject, and would seem to be a fairly com- 
mon species where guinea pigs are kept. It 
has not been met with in this country so far 
as records show, but may be looked for with 
great probability of success in any place 
where guinea pigs are kept in numbers. 
Denny characterizes it as “elongate, pale, 
fulvous-yellow, finely pubescent; head and 
SEM Bey 
\ 
edt pstmt erhual “OReKeing pe 
/ 
i i 3 | 
Fic. 140.—Gyropus ovalis—en- thorax darker, segments of the abdomen ) 
: larged (after Denny). : 
~ pkuaeloaitgeat with transverse striated fascia at the sutures; 
tarsi and ungues very short and minute.” Collected at Baltimore by 
Dr. A, Hassall. | 
