4 PEOCEEDINGS OF THE NATIOlSrAL MUSEUM vol.73 



lobes and a smaller inconspicuous dorsal lobe. The rays are well 

 separated and extend to near the edge of the bursa. The ventro- 

 ventral and latero-ventral rays are divergent and about equal in 

 size; the externo-lateral ray is slightly thicker and longer than 

 the other rays; the medio-lateral and postero-lateral rays are 

 divergent; the externo-dorsal rays arise from the base of the 

 dorsal ray and are curved dorsad near their posterior third; the 

 dorsal ray forms two branches near its tip and each branch is bidigi- 

 tate. Prebursal papillae present. The spicules are equal in length, 

 slender, modified tubular in shape, and 532/x long. The tips of the 

 spicules are pointed and incurved, and have a sharp pointed process 

 on the median aspect a short distance from the tip. The shaft of 

 each spicule appears twisted about 156ju, from its anterior end. The 

 gubernaculum is elongated, curved, well chitinized, and is 128/* long. 

 The telamon is composed of two similar, feebly chitinized, retort- 

 shaped structures, embedded in the ventral and lateral walls of the 

 cloaca. (Fig. 10.) The genital cone is small, rounded, and bears 

 two prominent papillae ; these papillae are pedunculated and are situ- 

 ated on each side of the cloacal aperture. 



Female 14 mm. long and with a maximum width of 166/*. The 

 vulva is situated about 2.7 mm. from the posterior end of the body. 

 The tail (fig. 11) is slender and pointed. The anus is located about 

 160/x from the end of the tail. The ovejectors (fig. 12) are strongly 

 muscular and have a combined length, including sphincters, of 400/*. 

 The eggs are oval, 64/* to 70/* long by 32/* to 38/* wide, with shells of 

 uniform thickness, and are not embryonated within the uterus. 



Host. — Three-toed sloth, Bradypus sp. 



Location. — Small intestine. 



Locality. — Central America (Penonome, Panama). 



Type specimens. — ^United States National Museum Helmintho- 

 logicai Collections No. 27003. 



This species differs from GrapMdiutn strigosmn (Dujardin, 1845), 

 the type of the genus, in the following respects : In G. strigoswn the 

 spicules, according to Hall (1916), are tubular and measure 1.2 to 

 2.4 mm. in length ; in G. hrowni they are modified tubular and their 

 length is only about one-half of the minimum length given for 

 G. strigosum. The gubernaculum in G. hroioni is long and well chiti- 

 nized ; in G. stHgosum it is short and so imperfectly chitinized as to be 

 almost invisible. In G. strigosum the diameter of the female dimin- 

 ishes abruptly behind the vulva; in G. hrowni the attenuation is 

 gradual. The cuticular inflation of the cephalic extremity is very 

 distinct and coarsely striated in G. hrowni, but this ciiaracter is not 

 mentioned for G. strigoswn. An examination of the specimens of 

 the latter species, donated to the Bureau of Animal Industry by 



