NO. 2131. NEMATODE PARASITES OF RODENTS— HALL. 223 



worm should be transferred from the genus Strongylus to Splroftera^ 

 but in default of any contradictory indications his latest choice is 

 followed instead of the earlier one. 



NEMATOIDEUM DIPODIS-TETRADACTYLI Creplin, 1844. 



Specific diagnosis. — None. 



Host. — Scarturus tetradactylus {Dipus tetradactylus). 



Location. — In abdominal cavity, the stomach, the walls of the 

 stomach, and the cecum. 



Locality. — Germany ( Breslau ) . 



This record is placed here on the chance that it might be a larval 

 member of the Filarioidea. There is no more likelihood of this, 

 probably, than there is that it is a member of the Strongyloidea. 

 The name Nematoideum is noncommittal, as it is a collective group 

 name without generic status or type species, and is erected for the 

 reception of species that can not be referred to any existing genera. 



SPIROPTERA species von Linstow. igoi. 



Specific diagnosis. — None. 

 Host. — 'Mus species {'"'' Mus minimus''^). 

 Location. — Stomach. 



Locality. — Nyassa Lake, German East Africa. 

 Von Linstow states in comment that the material covered by this 

 record was sexually undeveloped. 



SPIROPTERA species Gerstaecker, 1866. 



SynonyiVyS. — Spiroptera species Bakody, 1866; Tnchina hakodyii 

 Cobbold, 1879. 



Specific diagnosis. — Spiruridae (?) (p. 190) : Cysts 610 to 700 /it 

 long and 520 [i. thick. The coiled-up worm in the cyst occupies a 

 lumen 350 to 370 [i, in diameter, while the cyst wall is 100 to 120 \f, 

 thick (fig. 288). The larva is 1.4 mm. long and 100 to 110 [x thick. 

 The body appears compressed rather than slender. It narrows 

 close to the anterior end and attenuates to form a conical termi- 

 nation posterior of the anus. The cuticle is transversely striated. 

 On each side of the mouth aperture the head projects in a small, 

 pointed, conical, sharply contoured papilla (fig. 289). The anal 

 aperture is ventral, but it lies toward the periphery in the coiled-up 

 worm in the cyst and so gives the impression of being dorsal. The 

 tail ends in a knob-shaped process bearing on its surface small 

 conical spines (fig. 290). One specimen shows seven of these on the 



