466 MYEIAPODA 



S. immaculata * (Newport) (Fig. 723). The last dorsal plate with 

 a very deep, median cavity; second plate deeply emarginate behind; 

 antenna with 19 to 50 joints; length up to 7.5 mm.: Massachusetts to 

 Texas, in old stumps, under moss, etc.; Europe. 



S. nivea (Scopoli) (S. gratiae Ryder). No deep cavity in the last 

 dorsal plate, each segment with a pair of long setae projecting straight 

 out from body; second plate with the hinder margin straight or nearly 

 so ; length 2.5 mm. : eastern United States ; Europe. 



2. SCOLOPENDRELLA Gervais. Posterior margin of all the dorsal 

 plates except the last in form of a pair of triangular plates; head not 

 sharply separate from the trunk; first pair of legs often rudimentary: 

 12 species, 2 American. 



S. texana Hansen. Length 2.8 mm.; antennae with 19 to 22 joints; 

 cerci with a few long setae on the lower side, while all the other setae are 

 short; last pair of legs with 3 long dorsal setae on the penultimate 

 joint and 4 or 5 on the last joint : Austin, Texas. 



S. pusilla Hansen. Length 1.7 mm.; antennae with 14 joints; last 

 pair of legs with 2 long dorsal setae on the penultimate joint and 3 on the 

 last joint : Austin, Texas. 



SUBORDER 2. PAUROPODA.f 



Minute myriapods in which the body consists of a head and 12 

 segments, the latter being covered in most cases by 6 large dorsal plates 

 and bearing 9 pairs of legs, each of which has a single terminal claw; 

 each antenna consists of 4 basal segments and 2 terminal branches, 

 one of which is larger than the other and ends with 2 flagella and either 

 a stalked or a sessile round knob; one pair of maxillae, which form an 

 underlip; eyes absent; 4 or 5 pairs of long tactile bristles project from 

 the sides of the body; heart and respiratory organs wanting; genital 

 pores just behind the second pair of legs, being paired in the male and 

 simple in the female; young born with only 3 pairs of legs: 2 families, 

 2 genera, and 6 species, 3 being American; they live in woody places, 

 under stones, etc. 



FAMILY 1. PAUEOPODIDAE. 



Body elongate and cylindrical, with long legs projecting laterally 

 beyond the trunk; color white; each dorsal plate with 2 transverse rows 

 of bristles: 1 genus. 



* See "Habits and Structure of Scutigerella Immaculata (Newport)," by S. R. 

 Williams, Proc. Bost. Soc. Nat. Hist., Vol. 33, p. 461, 1907. 



t See "A New Genus of Minute Pauropod Myriapods," by J. H. Ryder, Am. Nat, 

 Vol. 13, p. 603, 1879. "The Morphology and Classification of the Pauropoda," by 

 JT. C. Kenjon, Tufts College Studies, No. 4, p. 77, 1895.. 



