MEMOIRS OF THE NATIONAL ACADEMY OP SCIENCES. 



45 



hairs on each ventral segment. Male with the second ventral segment triangularly excised; female with two small 

 holes; palpi thin, longer than the body by about the length, of their fingers; hypopodium oblong, incurved; tro- 

 chanter short, enlarged at tip, incurved, about half as thick as long; femur very long, straight, cylindrical, slender, 

 a little convex above before the tip, as long as the thorax and the three basal segments of the abdomen ; tibia similar 

 to trochanter, incurved, enlarged at tip, less than 

 half as long as the femur ; chela thin, one-half longer 

 than the femur ; the hand as thick as the tibia, cylin- 

 drical, a little enlarged below just beyond the artic- 

 ulation, straight, shorter than the femur; fingers as 

 long as the femur; slender, straight, viewed in pro- 

 file a little incurved, the tips hooked suddenly, the 

 movable finger a little shorter; both with a 6eriesof 

 sharp teeth inside; legs slender, the two anterior 

 pairs as long as the body, the two posterior pairs ex- 

 tending beyond the body the length of the tarsus; 

 hypopodia oblong, a little incurved, those of the 

 first pair a little pointed before; trochanter short, a 

 little longer than thick; femur long, cylindrical, 

 tibia half as long as the femur; first tarsal joint as 

 long as the tibia, second as long as the femur; the 

 two posterior pairs with the trochanter and base of 

 the femur enlarged; femur with a spurious articula- 

 tion before the middle ; first tarsal joint shoi ter than 

 the tibia; all legs with long fine hairs; two very 

 slender and strongly-curved booklets on tip; between 

 them an anchor shaped plantula with a thin cylin- 

 drical stem. The palpi of female are as long as those 

 ofthemale. Length 2.3 mm =.09 inch. Habitat: Wy- 

 andotte Cave, Indiana; five males, one female, in 

 alcohol. The female has a small external indentation 

 of the movable finger of the mandibles; the finger of 

 the males has no indentation, but in two specimens 

 the tip is somewhat broader, more obliquely cut, and 

 with a fine engraved line where the indentation 

 should be.'" 



The discovery of this blind Pseudoscorpion iu 

 America is very interesting. It belongs without any doubt to Schicedte's genus Blothrus, which, on careful exami- 

 nation, proves, however, to be merely Chthonius with undeveloped eyes, and is the smallest species known. 



" C. (Blothrus) sjiclwus differs by the longer tibia of the palpi, and by the two anterior pairs of legs with a two- 

 jointed tibia. The last statement is doubted by Mr. Simon, but Mr. Schicedte's accuracy is so well known that his 

 statements are to be accepted. (B.) abeillii has much longer palpi and legs, and the sexes of dissimilar development. 

 (B.) brevimanus is only known to me by an insufficient diagnosis. (/>.') ceplialntes seems rather similar to (B.) paokardi, 

 only a little larger, the mandible granulated, nearly as long as the thorax; the fingers of the palpi equally longer." 

 Another form, with two eyes, occurs in the Mammoth Cave: 



"It is pale yellowish; the thorax, mandibles, palpi, legs, and segments of the abdomen about the same color 

 the base of the mandibles a little darker, the abdomen between the segments and on the sbles paler. 



"I have seen only three specimens in alcohol, all from the Mammoth Cave region, one couple from one locality 

 and a female from another locality. I have compared all very carefully with C. (Blothrus) paokardi from Indiana. 

 They are a little longer. 3 to 3.2 mm long, a little darker or perhaps a little less white, but all three have on each 

 side of the thorax one eye, distant from tho anterior border as far as the length of the diameter of the eye ; the movable 

 finger of the mandibles is not indented. The examination of all other details shows no difference. Habitat, from, 

 the bottom of Dome, Mammoth Cave, with dead bat, November 9, and Long Cave, near Glasgow Junction, Kentucky, 

 one mile from daylight, May 11." 



My specimens, two males and two females, from tho Eotundain Mammoth Cave, have each two eyes, which, how- 

 ever, vary in the convexity of the cornea, and are so faint as to be easily overlooked. The males are very white; one 

 of the females shows traces of an indentation on the mandibular finger. The male from which the figure was drawn 

 measures 3 mm in length, or, exclusive of the mandibles, 2.3 mm . The hairs upon thorax and abdomen, which are cor- 

 rectly represented in tho figure, differ slightly from the description of tho blind form, but they are probably variable. 

 To Dr. H. Hagen my grateful acknowledgments are due for invaluable aid and suggestions. I have added 

 nothing to his observations on Pseudoscorpions; tho portions indicated by quotation marks are copied almost ver- 

 batim from bis manuscript. 



Hagen states in his original notice in the Zoologischer Auzeiger, in which he speaks of the 

 present species as Blothrus packardi, that "it certainly belongs to Blothrus, Schieedte, and is the 

 smallest known species." 



Fig. 12. — Chthonius packardii: a, male enlarged fifteen times; b, man- 

 dible; c, serrula of the mandible; al, finger of the mandible; e, chela of 

 ptdipalp ; /, end of tarsus; g, plantula. — After Hubbard. 



