122 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 50. 



sixth of the total length. The vagina opens just anterior of the anus. 

 The ratio of the body length anterior of the vulva to that posterior 

 of the vulva is 600 : 11. Anterior of the anus is a semicircular swell- 

 ing, from which muscles proceed obliquely posteriorly to the dorsal 

 line. The vagina ends in another hemispherical swelling, in front of 

 %Yhich the cuticle is swollen for 890 \).. The eggs are (?) 14 by 7 ji. 

 in diameter. 



Host. — Procavia hrucei {Heterohyrax mossambica) . 



Location. — Large intestine. 



Locality. — Kukwa Lake, German East Afi-ica. 



The dimensions given for the eggs, " 0.014 mm. . . . 0.007 mm.," 

 seem very small for a worm this size, and it is possible that these 

 figures should be 140 by 70 p.. 



Railliet and Henry (1912«) have left the genus Deletrocephalus 

 Diesing, 1851(2, unplaced in the formation of tribes of Strongylinae. 

 An examination of the available figures and descriptions of the type- 

 species, D. dimidiatus Diesing, 1851, indicates that we have in it a 

 member of the Strongylinae in which the vulva is near the anus and 

 the uteri are convergent, as in the Cylicostomeae, but the ray struc- 

 tures are uncertain or contradictory. According to some figures, the 

 externo-dorsal and dorsal rays have separate origins- and according 

 to others they originate in a common trunk. According to von 

 Linstow's figure, the dorsal and externo-dorsal rays of Strougylm 

 {Deletrocephalus) hrachylairmis apparently have separate origins, 

 but it would be unsafe to say positively that this was the case. Noth- 

 ing is said as to the convergence or divergence of the uteri. It is not 

 certain that von Linstow's species and Deletrocephalus dimidiatus 

 are congeneric, and this is additional reason for leaving Deletro- 

 cephalus unplaced in this paper. 



STRONGYLUS LEMMI von Siebold, 1837. 



Synonym. — Nematoideum muHs-amphihii Rudolphi of Diesing, 

 1851. 



Speci-fic diagnosis. — None. 



Host. — Mus musculus or Arvicola amphibius {Mus amphibius, 

 Levvmas amphibius). 



Location. — Inguinal glands. 



Locality. — Not given. 



This species is based on a record of Redi (1708) . Rudolphi (1810) 

 records it under the heading " Vermes generis dubii " and with the 

 notation " Muris musculi vel amphibii," and says that he is unable to 

 determine from which species of mouse Redi collected it. Rudolphi 

 (1819) later lists it under the same notation, closing his paragraph 



