428 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



ten segments, C. ricJMrdsonti^ has fifteen. The second antenna" are 

 shorter, not equaling the length of the boch^; in ('. r ic ha rdsoncV they 

 are longer than the body. The sides of the body are nearly parallel, 



the head nearly, if not quite, as wide 

 as the ])roadest segment. In C. r/'c/i- 

 ardsoniv the body is widest in the mid- 

 dle and tapers toward each end; the 

 head is eonsideral)ly narrower than 

 the first body segment. In CI nicka- 

 jackennln the telson is long, with 

 slightly concave sides, and the uro- 

 pods are short, their basal segment is 

 enlarged at its distal extremity, and 

 the terminal segments are about as 

 long as the basal portion; there are 

 tufts of l)ristles at the ends of the ter- 

 minal segments and a ver}^ few rather 

 large bristles along the margins of 

 both basal and terminal segments. In 

 ^1 I'ichardsoniie the telson is convex 

 sided and shorter, the uropods are 

 very long and slender and thickly 

 covered with short bristles, 'the basal 

 segment is fully as long as the tel- 

 son, and the terminal segment half as 

 long. There are differences also in 

 the appendages, but the above are 

 sufficient for our purposes. 



Compared with the well-known C. 

 stygta, the specimens from Metcalf 

 seem to resemble that species rather than 61 ricJutrdsonse, but the 

 differences are great enough to show that it has descended from some 

 other, l)ut closely related, species of A.selkif^. In order that compari- 

 sons may readilv be made, I have prepared figures of the three species 

 mentioned and have copied Packard's figures of C. nlckajacke?ms. 



Family ONISCID^E. 



Genus PORCELLIO. 



PORCELLIO LiEVIS Latreille. 



This species was found in great abundance under stones a short dis- 

 tance from the entrance to the cave. The}^ were well known to the 

 natives of the region, and are used by some of them as a medicine to 

 produce an eruption in the case of hives, measles, and similar diseases. 

 The recipe calls for ''nine sow bugs crushed in a small quantity of luke- 

 warm water.'' The dose is taken internally, and is said to be ver}' 

 efficacious. 



SPECIES OF C.ECIDOTEA. 



Kttigia (Mam- 



.s/s (Metcalf, 



richardsouit' 



Fig. 5.— The th 



a Telson and uropoda of ('. 

 moth Cave). 



b Uropod of ('. nickajackf)) 

 Georgia). 



c Telson and uropoda of C. 

 (Nickajack Cave). 



d Gnathopod of C. nickajackensis (Metcalf). 



e Fifth pereiopod of 0. nickajackensis (Met- 

 calf). 



/ Fifth pereiopod of <'. richardsonie (Nicka- 

 jack Cave). 



(/ Fifth pereiopod of ('. styfjiu (Mammoth 

 Cave). 



