218 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 50. 



tremity, lateral view. 

 Enlarged. After Pa- 

 RONA, 1898. 



Female 17 to 32 mm. long and 1 mm. thick. The posterior ex- 

 tremitj^ is obtuse. The vulva is not prominent and is located near 

 the union of the anterior and middle thirds of the body. The small 

 eggs are spherical and are 16 to 22 fi in diam- 

 eter. 



Host. — Sciurus melanog aster. 

 Location. — Stomach and intestine. 

 Locality. — Island of Mentawei, 

 Parona (1909) states that there is a single 

 uterus extending posteriorly fiom the vulva, 

 " L'utero ad un solo tubo- e che si estende all'in- 

 FiG. 285.-Pm'SALOPTERA cjietro." Thls can hardly be accepted as cor- 



sciuRi. Anterior ex- , , . tt- h 



rect, even on Parona s authority. His figures 

 indicate that this is a species of Physaloptera^ 

 and it is more likely that one branch of a uterus 

 has been overlooked, a very simple matter, than that we have here a 

 sj^ecies with the other characteristics of Physaloptera^ but with a 

 single uterus. Incidentally it may be noted that the shape of the 

 eggs is unusual, and correlated with the small size it 

 suggests that the eggs observed, were immature. 



Subfaxnily ^RDXIKN^STIN AE Railliet and Henry, 

 1911. 



Subfamily diagnosis. — Spiruridae (p. 190) : Mouth 

 with two lips loading into a pharynx, which is 

 strengthened by cuticular ridges in the form of rings 

 or spirals. Spicules unequal, the longer several 

 times the length of the shorter. Four pairs of pre- 

 anal papillae. Eggs containing embryos when ovi- 

 posited. 



Type-genus. — Arduenna Railliet and Henry, 1911. 



Genus PHYSOCEPHALUS Diesing, 1861. 



GeneHc diagnosis. — Arduenninae (p. 218) : Body 

 elongated, tapering slightly anteriorly. Head 

 marked off from the remainder of the body by a 

 cuticular inflation ending abruptly in a circular line 

 a short distance anterior of the posterior end of the 

 pharynx. Extending from the base of the cuticular 

 inflation to about the middle of the body are six 

 lateral alae, three on each side, the middle wing of each side 

 being wider than the others. Mouth with two lips, each in- 

 cised to form three lobes and each lobe bearing one papilla. The 

 mouth communicates with an inconspicuous buccal cavity which is 

 without teeth, and this in turn opens into a relatively long and 



Fig. 2S6.— Physa- 

 loptera scruRi. 

 Bursa. En- 

 larged. After 

 Parona, 1898. 



