6s IJl'LLKTIX 1(5, UNITKI) STATES NATIONAL MUSEUM. 



• Genus II. — Cii.KTASi'is, ^^en. nov. 



Body slender, not nnu-li depi-esseil, more «'(>nvex that in f*(>hf(h'.s>nuH, 

 hnt not so niui'li as in Sci/foii(>tns. 



Vntennn' v. itli tlie tliiid and sixth joints eiiual, tiie latter stronijfly 

 swolh-n, second iind iit'th siiheiinal, Jbnith eijual to seventh and eighth. 

 Segments 20; hiteral phites distinct, but not iis in Poli/drsmiis, slightly 

 Jingled, serrate; dorsal phites smooth, excepting; a row of indistinct, 

 setij^erous tubercles along the anterior and posterior margins, no me- 

 dian, dorsal line; last acuminate. li»'pngnatoriaI ])ore ratln'r large, 

 l)laced (Ml a moderately hivge and round tuberck", near the outer bor- 

 der of the 5, 7, J), K), lli, i;J, 1."), 1(J, 17, IS, V,) <lorsal plates. Pairs of 

 feet, c?;i(>, $.'U. 



This genus is ndated to 1'olffile.stnuft and Scfftonotus. but can be easily 

 separated by the <'haracter of the dorsal ])lates. 



2. Chaetaspis albus, sp. nov. 



Wiiite tliroughout. Slender, small, slightly acuminate before. An 

 tenna' exceeding the width of body, subclavate. First dorsal plate 

 large, semiciicular, angles not produced, provided with live rows of 

 hairs. Other dorsal i)lati's with the ])osterior angles a little produced, 

 lateral nuirgins with 3-4 setigennis teeth; rows of hairs 2 to 3. Feet 

 ratlu^rlong, S crassate, 9 slightly crassate. 6 copulation foot e. ct, not 

 as in P(>li/<U'smi(s- composed of two pieces, tlie outer curving outwards 

 aiul then inwards so that the ends almost touch over the nu'dian line 

 of body, rather robust, somewhat flattened, the eml apparently divided 

 into three i>ieces — a small lobe, followed by a long and slender one with 

 the end turned sharply downward, aiul this by a large Hat bifid ]»iece; 

 inner piece narrow an<l thin, sickle shaped, the end curving up be- 

 tween the branched lobe of the outer piece; coxa^ with a lew long 

 hairs. Seventh dorsal plate enlarged. Length of body G-7.5""" ; width, 

 ().3-0.5""". 



Habitat. — Bloomington, Ind. 



I have examined four 9 9 and three (5 $. It seeuH to be nu)re under- 

 ground in its habits than the other sj>ecies of this family known to me. 

 1 have always found it under logs buried rather deep in the ground. 

 I thought at lirst this might be the young of some other Pi>lydvsmi<la\ 

 but having found several males and taken a pair in the act of copula- 

 tion, I have decided that it must belong to a new genus. 



Genus 111. — Soytonotus Koch. 



3. Scytonotus cavernarum, sp. nov. 



Allied to nodido.sHs Koch. Pure white throughout. Slender, some- 

 what depressed, acuminate anteriorly. xVntenna' exceeding the width 

 of the body, clavate. First (hnsal plate ellii)tical, angles sharp; scales 

 arranged in five, transverse series, anterior row sharj), setigerous, all 



