9 



as long, and thickly covered with short, fine hairs ; all the longer 

 spines are movable and tipped with reddish-brown, approaching to 

 black ; terminal half of claws black. 



Ovipositor riifo-testaceous, swollen at the base, flattened in the ter- 

 minal two thirds, nearly straight, slightly curved upwards and ensiform 

 at the tip, produced to a sharp point with fi\e or six serrations on the 

 lower edge of extremity of inner valves, but hidden by the outer 

 ones ; anal cerci tapering to a fine point, furnished, besides the short 

 hairs common to all the appendages, with exceedingly fine long ones, 

 shortening toward the apex.* 



Measurements. The Average of many Specimens. Ante- 

 rior femora, .54-inch ; ant. tibiae, .59-inch ; middle femora, .49-inch; 

 middle tibiae, .59-inch; posterior femora, .84-inch; posterior tibiffi, 

 1.08-inch; antennas (longest), 4-inch; maxillary palpi, .50-inch; 

 ovipositor, .52-inch; cerci, .26-inch; whole body (as curved), .66-inch. 



This species is the one inhabiting the Mammoth Cave of Ken- 

 tucky, and the adjoining White's Cave ; they were found throughout 

 the cave to the remotest parts (seven miles or thereabouts), though 

 not near the entrance, especially in damp, moist situations, where 

 they abound ; they were found in especial plenty about " Martha's 

 Vineyard," and in the neighborhood of " Richardson's Spring," where 

 they were discovered, jumping about with the greatest alacrity upon 

 the walls, where only they are found, and even when disturbed, cling- 

 ing to the celling, upon which they walked easily ; they would leap 

 away from approaching footsteps, but stop at a cessation of the noise, 

 turning about and swaying their long antennae in a most ludicrous 

 manner, in the direction whence the disturbance had proceeded ; the 

 least noise would Increase their tremulousness, while they were uncon- 

 cerned at distant motions, unaccompanied by sound, even though pro- 

 ducing a sensible current of air ; neither did the light of the lamp 

 appear to disturb them; their eyes and those of the succeeding 

 species are perfectly formed throughout, and they could apparently 

 see with ease, for they jump away from the slowly approaching hand, 

 so as to necessitate rapidity of motion In seizing them. Late In Octo- 

 ber, females were obtained enormously distended with eggs. 



Rapiiidophora stijgia, nov. sp. 



Body pale brown, with the segments bordered posteriorly with dark 

 brown or black, becoming gradually paler toward the hinder part of 

 the body, and dotted with pale spots. Head pale brown, a black 

 spot beneath each eye, and another midway between these. Eyes 

 black, subpyriform, subglobose. Appendages of the mouth dirty pale. 

 Antennte yellowish brown, paler toward tip, obscurely and distantly 



* A more detailed account of tbe abdominal appendages cannot be given till 

 tbe bomologies of these parts are carefully studied and their nomenclature 

 rectified. 



