122 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. IM 



The tarsus bears about 16 nonspecialized setae. On its dorsal 

 surface is a long, blunt, striated spur with a microspur just 

 proximal to it. On the posterior edge of the pretarsus is the 

 pointed, striated pretarsala. Two claws and an empodium similar 

 to those on leg I are attached to the end of the pretarsus. 



The coxa in leg III is separated from coxa II, the distance 

 increasing with engorgement. A single seta, usually, is attached 

 near its anterior margin. The form of coxa III and the attach- 

 ment of its seta vary slightly in different species. The trochanter 

 has a nonspecialized seta attached proximally at the anterodorsal 

 margin. The basifemur has two nonspecialized setae — a larger 

 dorsal and a smaller ventral. On the proximal dorsal surface of 

 the telofemur is a transverse row of three nonspecialized setae. 

 The genu has three nonspecialized setae spaced around it. Usually 

 there is a pointed, striated genuala on its dorsal surface. The 

 tibia has six nonspecialized setae spaced around it. In about 

 half the species a pointed, striated tibiala is found on the proxi- 

 mal half of its dorsal surface. The tarsus bears about 15 non- 

 specialized setae. One species has a long, nude, whiplike seta, a 

 mastitarsala. The tarsus terminates in a pair of claws and a 

 median empodium somewhat longer than those on legs I and II. 

 The scutum varies in size and shape among the species of 

 Euschongastia. Ornamentation varies also, but ridges and punc- 

 tae are usual. In some species the striated cuticle appears to have 

 encroached upon or to have folded over the posterior or lateral 

 margins. There are always five setae in addition to the sensillae. 

 Near the middle of the anterior margin is the anterior median 

 seta. At the corners between the anterior and lateral margins 

 are the anterior lateral setae. At the angles between the lateral 

 margins and the posterior margin are the posterior lateral setae. 

 These setae are clothed with setules. The five scutal setae gen- 

 erally resemble the dorsal setae. All Euschongastia have expanded 

 sensillae. The sensillae arise from the pseudostig-mata, which 

 are rather large and deep pits in the scutum. The slender, basal 

 pedicel may gradually become larger in diameter and blend 

 into the head of the sensilla; or it may increase very little and 

 be distinctly set off from the enlarged head. The enlarged head 

 is clothed with setules. In many species the posterior surface 

 of the sensilla bears fewer and heavier setules than the anterior 

 surface. For the determination of anterior and posterior sur- 

 faces, the sensilla is considered to be standing erect on the scutum. 

 The standard data of the scutum (fig. 3,c) , which are included 

 in descriptions of species, consist of measurements in microns 



