4 U. S. NATIONAL MUSEUM BULLETIN 212 



In 1872 Saussure and Humbert in their "fitudes sur les Myriapodes'* 

 {in "Mission Scientifique au Mexique") while dealing primarily with the 

 Mexican fauna, gave a complete list of the species known at that time from 

 the entire North American continent. In this work they recognized, without 

 naming, three suborders of Chilognatha of which their "I" corresponds to 

 the Pentazonia, "11" to the Polyxenidae, and "III" to the remaining families. 



Very influential and important to all subsequent work upon the diplopods 

 was that of Latzel in 1884, "Die Myriapoden der Osterreichisch-Ungarischen 

 Monarchic." His diagnoses and descriptions set a high standard for accu- 

 racy and clarity. These he founded more extensively than had previously 

 been done on important anatomical characters, emphasizing especially the 

 value of the copulatory appendages in diagnosis. In this classic work 

 Latzel used the term Diplopoda, as has been done subsequently by all others, 

 to designate the entire group of millipeds, which he divided into three sub- 

 orders: the Pselaphognatha for the Polyxenidae, the Colobognatha for 

 Brandt's Sugentia, and the Chilognatha for the remainder. 



Pocock in 1887 first elevated the Chilopoda and Diplopoda to the rank 

 of separate classes. He divided the Diplopoda into the two subclasses 

 Pselaphognatha and Chilognatha, and the latter into two orders, the Onis- 

 comorpha and Helminthomorpha (including the two suborders Polydes- 

 moidea and Juloidea). In America, BoUman, in his paper "Classification 

 of the Myriapoda" (U. S. Nat. Mus. Bull. 46, pp. 153-162, 1893), accepted 

 Pocock's classification down to the suborders, but reduced the Diplopoda to 

 the rank of a subclass and the Chilognatha to a superorder, and erected a 

 separate superorder, Podochila, for the Pselaphognatha. His complete sys- 

 tem may be summarized as follows : 



Subclass Diplopoda 

 Superorder Podochila 

 Order Pselaphognatha 



Family Polyxenidae 

 Superorder Chilognatha 

 Order Colobognatha 



Family Polyzoniinae 

 Subfamilies: 

 Siphonophorinae 

 Polyzoniinae 

 Andrognathinae 

 Platydesminae 

 Order Helminthomorpha 

 Suborder luluidea 

 Superfamily Juloidae 

 Family Julidae 

 Subfamilies: 

 Spirobolinae 

 Spirostreptinae 

 Cambalinae 

 Parajulinae 



