. —3— 



plates with posterior angles produced, especially posteriorly ; lateral margins three 

 or four toothed, indistinct posteriorly, tubercles distinct, arraiitjed in two rows of four 

 each, anterior border indistinctly divded in:o tv\ o, po>teiiorly, the last row of tub- 

 ercles project beyond border of ses^ments. l,-<^s lonir, crassate in male. 



Male : copulation foot very simi ar to .ft' rains ; ventral plates produced into a 

 short, pilose lobe anieriorly. 



Length of body lo — 14 mm., width 1.5 1 8 mm. 



Hab.— Little Rock. 



This species is described fiom a number of specimens found in the 

 low lands, south of Little Rock. 



14. Polydesmus pinetorum, sp. nov. 



Very similar to P. srrra/ns, hut the j^eneral color paler and sizj smaller. 

 Tubercuiatiuii not su distinct, sides ot first s.-gment I toothed, other distinctly 3 or 

 4 toothed. La>t row ol scale> on posterior segments composed of six or eight setae 

 tipped sc.iL--, wiiich project beyond border of Segments. Ventral plate of ninth pair 

 i,)t legs not produced as in ser rains, copulation foot very similar. 



Length of body 15 to 18.5 mm.; width 2.2 to 2.8 mm. 



Hab. — Little Rock, Arkadelphia, Okolojia, .Murfree-boro, and Ultima Thale. 



As ah'eady indicated, this species is closely related to serrafus. It is 

 principally separated by its smaller size and form of the ventral of ninth 

 pair of legs of male. 



This species may only represent a geographical form (j{ serrafus. It 

 is very abundant throughout the state, and all those collected during the 

 su'nmer were in the larva stages. I am indebted to Mr. Hutcherson for 

 adult specimens. 



15 Fontaria virginiensis (Drury). 



Abundant at Donaldson, common at Okolona. 



Specimens from Arkansas are similar to those from North Carolina, 

 but those from northern parts of Mississippi valley represent geographical 

 species. 



At Donaldson the adults were found crawling on the surface of the 

 ground in company with a large number of their young, probably one 

 adult to five or eight hundred young, then (July 11, 1887) about half 

 grown. 



This species seems to be more confined to river bottoms, and low 

 rich woodlands. 



The odor of prussic acid is strongly emitted by this species through 

 a series of pores on each side of the body. 



16. Sphaeriodesmus pudicus sp. nov. 

 General color pmkish, especially posteriorly, anterior half of segments darkest, 

 a black median dorsal line, antennas dark, legs pale. Body widest and highest an- 

 teriorly, tapering posteriorly, smooth, setee absent. Vertex smooth, somewhat sul- 

 cate. AnteniiK subclavate, about equalling width of body. Dorsal plates smooth, 

 tour preceding the last with an indistinct row of obtuse scales ; lateral plates except 



