Family 4. LITHOBIIDAE Newport. 



This family in some respects the highest of the Myriapoda, contains 

 two genera whose characters are given below. 



Ucelli 2 — 40 each side of head, variously arranged; labium 3-toothed in the 



middle Lithobius* Leach. iS sp. 



A single large ocellus each side of head; labrum 1-toothed in the middle 



Henicops Newport [Lstmyctes Meinert). 1 sp: 



I have followed Stuxberg and Latzel in uniting Bothropolys Wood 

 with Lithobius. 



This completes the list of genera as now known in North America; 

 species and probably genera are waiting discovery and description, for 

 as we shall soon show, large areas of our country are still untouched and 

 only very limited regions have been worked with any degree of thorough- 

 ness. The study of the Myriapods in America is only fairly begun. 



So far we have given only the number of species in each genus. 

 The following table will give a summary by families. For contrast tne 

 corresponding numbers for a much more limited European area are 

 given, namely Austro-Hungary where the Myriapod Fauna has been 

 thoroughly studied. The number of species already reported will be seen 

 to be 129, distributed among 27 genera. A few of these however repre- 

 sent species early and imperfectly described which may not certainly be 

 identified be recent writers. 



* S.uxberg (Ofversigt af k. Vetensk. Akad. Forhandl. 1875) has formed six 

 subgenera of Lithobius all of which are represented with us. I subjoin his diagnoses. 



1. Eulithobius Stuxberg. Scuta dorsualia 6, 7, 9, n, 13 angulis posticis pro 

 ductis. Pori coxales in pedum paribus 12, 13, 14, 15 (L. niultidentatus). 



II. — Neolithobius Stuxberg. Scuta dorsualia 7, 9, II, 13 angidis posticis pro- 

 duciis. Pori coxales in pedum paribus 12, 13, 14, 15 ,(L. vorax, L. mordax, 

 L. transmarinus). 



III.— Lithobius Leach s. str. Scuta dorsualia 9, 11, 13 angidis posticis prod mils. 

 Pori coxales in pedum, paribus 12, 13, 14, 15 (L. xanii, L. planus. L. forficatus, 

 L. paucidens, L. pinetoruin). 



IV. —Pseudolithobius Stuxberg. Scuta dorsualia 9, 11, 13 angulis posticis pro- 

 duciis. Pori coxales in pedum paribus 11, 12, 13, 14, 15 (i. megaloporus). 



V. — Hemilithobius Stuxberg. Scuta dorsualia 11, 13 angulis posticis productis. 

 fori roxales in pedum paribus 12, 13, 14, 15 (L. eucnemis). 



VI. — Archilithobius Stuxberg. Scuta dorsualia omnia angulis posticis roiundatis 

 vel subrectis. Pori coxales in pedum paribus 12, 13, 14, 15 (L. bipunctata, L. 

 monticola, L. pusio, A. Kochii, L. obesus, L. paradoxus, L. bilabiatus). 



