THE MYRIAPODA OF NORTH AMERICA. 37 



Type. — U. 8. Nat. Museum. 



Habitat. — Indianapolis, Iud. 



Description of type. — Brown, legs and under parts paler. Slender, 

 scarcely attenuated anteriorly, moderately shining. First dorsal plate 

 transversely suboval, tubercles 10-6-8, seta? tipped; lateral margin one- 

 toothed. Tuberculatum of anterior segments rather indistinct, 4-4-G; 

 posteriorly the first row is more obliterated, the second is usually com- 

 posed of six tubercles, and those of the last row are acute and project 

 beyond posterior border of segment; lateral margins three or four 

 toothed. Legs long. 



Male: Legs strongly erassate, last four joints tuberculate beneath; 

 coxa of second pair much produced and the end of lobe pitted ; femur 

 not much swollen above; genitalia very similar to P. inconstans Latzel. 



Length of $ 11.6 mm , width of first segment 1.1""", width of tenth, 

 1.3 mm ; 9 length 8.5 mm , width of first segment, 8 n,m , width of tenth 

 segment 1""". 



This species is very closely related to the European Polydesmus in- 

 constans Latzel, as is shown by the tuberculatum and the form of male 

 copulation foot, while it only resembles P. moniliaris Koch in tnber- 

 culation. 



I have examined a male and a female, collected by Mr. Frederick 0. 

 Test, my friend and fellow- student, for whom the species is named. 



6. Polydesmus braimeri, sp. no v. 



? f Polydesmus pennsylvanicw Koch, Syst. d. Myr., 133, 1847 (Pennsylvania) ; Koch, Die 

 Myriopoden, ii, IS, pi. 69, tig. 112. 1863. 



Diagnosis. — Very similar to Polydesmus serratus Say,* but body more 

 depressed and attenuate anteriorly; antenme and legs more slender 

 and in the male less erassate. 



Type. — U. S. Nat. Museum. 



Habitat. — Mossy Creek, Jefferson County, Tenn. 



As the characters of P. serratus vary exceedingly in respect to size 

 and form, I have had considerable trouble iu using characters exact 

 enough to distinguish P. branneri from the various forms of P. serratus. 

 The most important differences by which P. branneri is separated from 

 P. serratus are those of the male genitalia; but as it is almost impossi- 

 ble to give a good definition of these characters, I have thought it best 

 to say nothing now, but wait until I can have good figures made. 



Concerning the male genitalia of P. serratus, I may say that in all 

 the specimens I have examined from Minnesota, Illinois, Indiana, 

 Pennsylvania, and North Carolina, I find that the characters are essen- 

 tially similar, the only important variation being in the number of plate- 

 like spines. I have thought that P. branneri may be identical with 



"Polydesmus serratus Say, Journ. Phila. Acad. Nat. Sci., 106.1820 = P. canadensis 

 Newport, Ann. and Mag. Nat. Hist., 205, 1844 (Hudson's Bay) =P. glaucesens Koch, 

 Syst. d. Myr., 133, 1847 (North America). t P. pennsylranicus Koch, Syst. d. Myr., 

 133, 1847 (Peuusylvania). 



