350 MALLOPHAGA 



221), which is said to have been figured by Redi two hun- 

 dred years ago under the name of Pulex 

 capi. This species multiplies to a con- 

 siderable extent ; it is of very active 

 habits, and passes readily from one bird 

 to another, so that it is found on other 

 species besides the domestic fowl. It is 

 even said that horses kept near hen- 

 roosts have been seriously troubled by 

 Menopon pallidum, but it is suggested 

 by Osborn that these attacks may per- 

 haps have been really due to itch-mites. 



FIG. 221. Menopon pallidum ; ,, . , , . , . 



inhabits the common fowl, There is, however, no doubt that this 



Gaiius domesticus. (After species may infest poultry, especially if 

 sickly, to an enormous extent. The dust- 

 baths in which poultry are so fond of indulging are considered 

 to be of gteat use in keeping down the numbers of this Insect. 



A table of the birds and mammals on which Mallophaga 

 have been found, together with the names of the latter, has been 

 given by Giebel. 1 The classification of the group, so far as the 

 principal divisions are concerned, by no means accords with the 

 kind of animals that serve as hosts, for the only two genera 

 peculiar to quadrvipeds (Trichodectes, Fig. 220; and Gyropus) 

 belong to the two chief divisions of Mallophaga. The genus 

 Menopon includes numerous species found on birds, and three or 

 four others peculiar to mammals. 



Two very natural divisions, Philopterides and Liotheides, were 

 adopted by Griebel and Nitzsch, but unfortunately the chief 

 character they made use of for diagnosing the two groups the 

 presence or absence of maxillary palpi was illusory. Apparently 

 the labial palps will serve the purpose of distinguishing the 

 two divisions, they being present in the Liotheides and absent in 

 the Philopterides. A table of the characters of the avicolous 

 genera of these two groups is given by Grosse. 2 



The Liotheides are more active Insects, and leave their host 

 after its death to seek another. But the Philopterides do not 

 do so, and die in about three days after the death of their host. 

 Possibly Mallophaga may be transferred from one bird to another 



1 Op. cit. pp. vii.-xiv. For classification, etc., see also Piaget, Les Pediculiiies. 

 Leyden, 1880. 2 Zeitschr. wiss. Zool. xlii. 1885, p. 532. 



