NEMATODOS PARASITOS DE LOS BATRACIOS DE MEXICO. IV.

Resumen

In te present paper we re-describe two species of parasitic Nematodes from the Amphiibians of Mexico and we describe the male of Spironoura cryptobranchi which Walton cauld not describe for lach of specimens.
The first re-description is the one of a Nematode from the lung of Bufo marinus L . identified as Rhabdias sphaerocephala Goodey
1924, wich although somewhat similar to R. fá¼lleborni could not be identified as this last species because of the absence of chitinous protection in the buccal capsule and of the vulva in the pre-equatorial region.
The second re-description corresponds to a parasite from the intestine of the "axolotl" Rhyacesiredon altamirani (Dugés) identified as Spironoura cryptobranchi Walton, 1930.
New hosts and areas of geographic distribution are mentioned.