216 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



bular portion of peritreme extends to level of midpoint of coxae 

 II. Epistome narrow and pointed with 10 to 12 fimbriae on each 

 lateral margin ; some fimbriae simple, others branched doubly or triply. 

 Chelae of about equal length; each nearly straight, bent sharply at 

 tips. Fixed chela with a bifid tip and two teeth; a distal seta im- 

 mediately posterior to the tip and a proximal seta at the base of the 

 chela. Movable chela bent at nearly a right angle at its distal end 

 and with two teeth. Maxillae distinctive in outline ; all but anterior 

 pair of maxillary setae barbed. Palpi only slightly tapering; coxa 

 with an especially strong ventral, medially directed seta, which is 

 barbed on one side ; most setae on palpi barbed except those on tarsi ; 

 anterior margins of at least coxae, trochanter, and femur serrated. All 

 setae of legs, except terminal tarsal setae, barbed ; distal margins of 

 all segments, except tarsi, serrated. Tarsal length-width ratios are : 

 Leg I 5.5 : 1, leg II 4.5 : 1, leg III 6 : 1, leg IV 8 : 1. 



Male. — Distinctly smaller and narrower than female. Dorsal shield 

 covers almost entire dorsal surface. Setae on ventral shield correspond 

 to those of female, including the single pair of accessory setae on its 

 anterior margin. Usual genitoventral setae very little larger than 

 accessory setae of genitoventral region ; shield greatly expanded pos- 

 terior to coxae IV and extending laterally and anteriorly to posterior 

 ends of the peritremes; pores on shield correspond to those of the 

 female in size and position. Metapodal and endopodal shields in- 

 cluded in ventral shield. Peritreme and epistome as in female. 

 Chelae greatly modified. Fixed chela toothless and without a seta. 

 Movable chela much larger and divided near its proximal end into two 

 branches, the dorsal of these in turn divided into two prongs distally. 

 Maxillae as in female except that lateral horns are more blunt ; as in 

 the female, the anterior pair of maxillary setae are smooth. Palpi 

 and legs as in female. 



Nymph.— Body relatively shorter than in adults ; a slitlike invagina- 

 tion on each side of dorsal shield at level of coxae IV; setation of dor- 

 sal shield as in adults except that setae may not be quite so numerous. 

 Tritosternum and presternal area as in adults. Ventral shield ex- 

 tends to level of midpoint on coxae IV and bears four pairs of setae, 

 representing the three pairs of usual sternal setae and the single pair 

 of metasternal setae. The usual genitoventral setae flank the pos- 

 terior end of the shield. As in adults, the anterior pair of usual 

 sternal setae are barbed and are thicker than the others. Sternal 

 pores located as in adults. Anal shield with only four setae : the three 

 usual anal setae and the most anterior accessory seta; the posterior 

 usual anal seta is the largest and is the only barbed seta on the shield. 

 Ventral body setae as in adults. Peritreme not well chitinized. 

 Epistome, mandibles, and maxillae as in female. Palpi as in adults 

 but relatively stouter. Legs relatively stouter than in adults. 



