NEW MALLOPIIAGA. 59 



ized, of a racial condition, but of a specialization, albeit 

 in the line of reduction or degradation. With the simple 

 general structure there goes a highly concentrated ner- 

 vous system, greatly modified mouth parts, and curiously 

 specialized antennas. 



The thorough study of the life-history, embryonic and 

 postembryonic, is needed to throw more -light on the po- 

 sition of the Mallophaga. Till such study is made, the 

 present isolated position assigned the group, based on the 

 known structure of the adult and on its habits, may be 

 accepted as representing the consensus of authority. 



Classification. 



The Mallophaga were divided by Nitzsch into two fam- 

 ilies, the Philopteridas, with filiform antennas and without 

 maxillary palpi, and the Liotheidas, with capitate 4 -seg- 

 mented antennas and maxillary palpi. The family Phil- 

 opteridas included two genera, Trichodectcs, with 3 -seg- 

 mented antennas and i-clawed tarsi, and Philopterus, with 

 5 -segmented antennas and 2 -clawed tarsi. The latter 

 genus was subdivided into the five subgenera, Docopli- 

 orns. JVtrmus, Goniocotes, Goniodes, Lipcurus. The 

 family Liotheidce similarly included two genera, Gyropits, 

 with 1 -clawed tarsi, and JLtotheum, with 2 -clawed tarsi. 

 The latter genus was subdivided into six subgenera, Eu- 

 reiou, Lcemobothrium, Physostomum, Trinoton, Colpo- 

 cephalum and Menopon. The two i-clawed genera Tri- 

 chodectcs and Gyropus were found by Nitzsch exclusively 

 upon mammals; all the other genera exclusively upon 

 birds. 



In essential identity the classification of to-day is that 

 of Nitzsch; it differs in discarding the generic groups 

 Philopterus and Liotheum, and in considering the Nitz- 

 schian subgenera as genera, and in the addition of sev- 

 eral new genera. 



