NBOTEOPICAL SPECIES. 187 



a free portion bearing the spine and a larger basal part. The 

 basal part is cylindrical^ and the terminal portion often of 

 considerable size. Those immediately round the lips appear to 

 be without this characteristic. 



The antennae present no features of specific interest. The 

 tongue and lips are without pigment and have the typical 

 form. 



The jaws present diflPerential characters. The outer blade 

 (fig. 26) has a well-marked minor tooth in addition to the 

 main one. On the inner blade the number of minor teeth 

 varies (generally eight) , and the anterior of them is close to the 

 main tooth and larger than the rest, which are separated from 

 it by a diastema (fig. 25). 

 The oral papillae are normal. 



A typical ambulatory appendage presents the following 

 characters (fig. 12). The leg possesses four spinous pads, a 

 strongly marked, rather deep groove in the position of the 

 tumid papillse of Capensis, i.e. a groove placed on the ven- 

 tral surface of the leg, and extends from the opening of the 

 nephridium as far as the third or fourth row of papillae from 

 the proximal pad. This groove may be widely open as in the 

 leg figured, or its edges may be approximated so that it appears 

 as a slit. The papillae at its margin are somewhat larger and 

 more indistinct than the ordinary papillae. The foot resem- 

 bles that of Capensis in possessing two papillae on its 

 anterior face, but the two basal papillae are absent. 



The opening of the segmental organ of the fourth and fifth 

 legs is on a papilla which is placed on the proximal side of, and 

 quite separate from, the third pad, between it and the proximal 

 pad (fig. 11). This feature is found in all the neotropical 

 species which I have examined. On certain of the posterior 

 legs of the males there are two and sometimes one smooth 

 white tubercle with an opening at their extremities (fig. 22). 

 They are placed close behind the groove, and are found only 

 on the posterior legs. Their exact arrangement varies in 

 different individuals. To give examples : 



