chamberlin: the chilopoda of brazil. 171 



Branchiotrema Kohlrausch, Journ. Mus. Godef., 1878, p. 70; Archiv. naturg., 



1881, 47, 1, p. 70. 

 Parolostigma Pocock, Biol. Ceutr. Anier. Chilopoda, 1895, p. 25. 



Of this genus nine species are at present known from Brazil, five 

 of these being here described as new. 



Key to Species. 



a. Tarsal spines wholly absent or, rarely, a few of the legs with a 



much reduced spine 0. limhatus (Meinert) . 



aa. Tarsal spines present and distinct. 



b. Dorsal plates of caudal half of body distinctly scabrous, 



bearing rows of fine elevated spinous points. 



c. Last ventral plate without distinct median sulcus; only 



the two proximal articles of the antennae glabrous; with 



five rather small keels or keel-like elevated lines on dorsal 



plates of caudal portion of the body.. .0. casus, sp. nov. 



cc. Last ventral plate with a distinct median longitudinal 



sulcus; two and a fourth or two and a half proximal 



articles of antennae glabrous; only a single, flat, median 



keel present on dorsal plates. 



d. Twentieth legs without a tarsal spine; only one tooth 

 on each dental plate distinct, the others being com- 

 pletely fused; head and first dorsal plate abruptly 

 different in color from the other plates, brownish. 



0. rex, sp. nov. 



dd. Twentieth legs with a tarsal spine; each, dental plate 



with four distinct teeth; head and first dorsal plate 



not abruptly different in color from the other plates, 



olivaceous 0. scabricaudus Humbert et Saussure. 



bb. All dorsal plates smooth, those of the caudal half of the body 

 not distinctly scabrous, 

 c. First eighteen or nineteen pairs of legs with two tarsal 

 spines. 



d. First eighteen pairs of legs with two tarsal spines; 

 twentieth legs with a tarsal spine; dorsal plates with 

 a conspicuously elevated double keel each side of 

 middle, the dorsal sulcus of each side lying between 

 the halves of this keel 0. tidius, sp. nov. 



