12 IXODOTDEA, OR TICKS, OF THE UNITED STATES, 



In 1800 Dr. Georo^e Neumann, of Toulouse, France, began the pub- 

 lication of a Revision of the IxodicUc. Doctor Neumann attempted 

 to monograph the ticks of the entire world, a task which in 1890 

 doubtless seemed quite possible, and the " Revision " was completed in 

 four parts. Since then he has examined thousands of specimens, and 

 his studies have appeared in five notes on the Ixodidaj supplementary 

 to the " Revision." It is quite natural that in examining such a host 

 of specimens from all parts of the world at varying intervals he 

 should be inclined to unite forms which to the student of local faunae 

 seem abundantly distinct. It is in this way that I differ from Doctor 

 Neumann as to the species occurring in this country. I have seen 

 practically all the material that he studied from the United States, 

 including most of his types, and also collections from many colleges 

 and other institutions in this country, together with larger collections 

 made in the past few years. The types of Say and Fitch are lost, 

 but through the kindness of Mr. Samuel Henshaw I have examined 

 the types of Packard, now in the Museum of Comparative Zoology. 

 This enables me to place correctly several species hitherto misplaced 

 by authors. In 1899 Doctors Salmon and Stiles published a finely 

 illustrated W'Ork on the cattle ticks of the United States. At that 

 time their material was largely in Doctor Neumann's hands, and since 

 then several species have been collected in this country, and Neumann 

 himself has changed his opinions regarding several species. 



During the past j-ear Messrs. W. D. Hunter and W. A. Hooker, of 

 this Bureau, have issued a bulletin (No. 72) on the cattle tick and 

 other species, with much ethologic matter and valuable breeding 

 notes. In this paper 38 species are recorded from this country, and 

 3 unplaced forms, doubtless identical with some of the known species. 

 More species are to be expected in Ixodes^ so that our tick fauna may 

 yet have 50 species. 



CLASSIFICATION. 



Latreille, in 1795, made two genera for the ticks, Argas and Ixodes. 

 The striking differences l)etween the two were I'ecognized by follow- 

 ing acarologists, some of whom even placed A7'gas Avith the Gamasidfe. 

 Koch, in 18M, divided these two genera into ten — just about as they 

 stand to-clay. He arranged these ten genera within three families — 

 Argasidse, Ixodida> (long palpi), and Rhipistomidse (short palpi). 

 These three groups have been generally adopted bj^ later authors. 

 Neumann has modified it somewhat by using rostrum long or short 

 to separate the last two families. But this wnll hardly distinguish 

 some species of Amhlyornnia and Dermacentor. Doctor Marx, in 

 1892, made a somewhat different arrangement, dividing the group 

 into two — Catastomata and Antistomata. The former is the Arga- 

 sida^ of Koch, the later he separates into tln'ee families — Ha:'malas- 



