10 



annulated with narrow pale bands ; first joint with a central faint 

 brown annulation, shaped as in subterranea, but less flattened and 

 truncated ; second joint very small, with lateral constrictions ; third 

 joint as long as first, cylindrical ; fourth joint half as long as third ; 

 remainder unequal but very short, and continuing of the same average 

 length, while they become more slender toward the extremity. Last 

 joint of maxillary palpus split interiorly almost its entire length. 



Lateral edges of thoracic segments minutely marginate ; the pro- 

 notum is bordered in front as well as behind with brown, and is 

 irregularly mottled with black and dirty yellow. Legs pale-yellowish, 

 femora and tibiae and joints of tarsi beneath, especially at extremities, 

 more or less clouded with brown. Coxfe as in suUerranea ; there are 

 three or four distant spines on the upper part of the inner edge of 

 anterior femora, and upon the upper part of both posterior edges of 

 middle femora ; the internal terminal lobes of the middle femora 

 also gives rise to a short spine ; spines on under side of four anterior 

 tibiae, same as in suhterranea^ except that the spines of the parallel 

 rows are opposite or nearly so. Posterior femora barred and cross- 

 barred with dark brown bands ; beneath, two rows of serrations or 

 rudimentary spines ; tibife as in suUerranea ; spines and claws tipped 

 with reddish brown. 



Ovipositor brown ; thickened at base, flattened posteriorly, nearly 

 straight, very slightly curved at the end, the tip with a dull point ; 

 inner valves at their extremity waved beneath into three or four dull 

 points, hidden by the outer valves. Anal cerci brown, beset with long 

 delicate hairs, as in suUerranea. 



Measurements. Average of many Specimens. Anterior 

 femora, .34-inch; ant. tibiae, .36-inch; middle femora, .31-inch; mid- 

 dle tibiae, .35-inch ; posterior femora, .71-inch; post, tibiae, .76-inch ; 

 antennae (longest), 3.44-inch; maxillary palpi, .33-inch; ovipositor, 

 .51-inch; cerci, 25-inch; body (as curved), .80-inch. 



Nearly opposite Hickman's Landing, upon the Kentucky River, there 

 is a large cave, a mile or more in extent, which has received no name ; 

 quite near it, farther up the river, is a much smaller one, a few hun- 

 dred feet only in extent ; in this latter place the stygia is found, — for 

 convenience' sake we may call it " Hickman's Cave ; " though search 

 was made in the larger cave, no Rhapliidopliorce were found, but in the 

 remotest corner of Hickman's Cave, in a sort of hollow in the rock, 

 not particularly moist, but having only a sort of cave-dampness, the 

 stygia was found plentifully ; these were also found exclusively upon 

 the walls. Even the remotest part of the cave is not so gloomy but 

 that some sunlight penetrates it. 



The relations of these cave-insects to other Raphidophorce are very 

 interesting. 7i. stygia inhabits a cave only a few hundred feet from 

 the sunlight ; R. suUerranea deep caves, scarcely ever within a mile 



