464 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 58. 



QUADRIGYRIDAE, new family. 



Acanthocephala of medium size parasitic as adults in the alimen- 

 tary canal of fishes. Anterior body region provided with cuticular 

 spines. Proboscis receptacle enclosed by a single muscular wall. Cen- 

 tral nervous system located near the base of the receptacle. Subcu- 

 ticular nuclei in anterior region elliptical, in sagittal plane; in re- 

 mainder of body a iew large, branched nuclei, laterally arranged. 



SUMMARY. 



1. A collection of Acanthocephala taken by Prof. A. S. Pearse from 

 fishes of Lake Valencia, Venezuela, contains two new species, each of 

 which represents a new genus and one of them a new family. 



2. PandosentWj new genus, is described and P. iracundus, new spe- 

 cies, is designated as type. Aquide7is fulcher is the type host. 



3. The relationships of the genus Pandosentis are discussed. 



4. Quadrigyrus^ new genus, is described and Q. torquatus, new spe- 

 cies, is designated as type. Hoplias malaharicus is the type host. 



5. The relationships of the genus Quadrigyms are discussed and a 

 new family, the Quadrigyridae, is established with Quadrigyms as 

 the type genus. 



LITERATURE CITED. 



DiEsiN'G, K. M. 1851. Systema Helminthium. Vidobonae, 1850-1851. 

 Graybill, H. W. 1902. Some points in the structure of tlie Acanthocephala. 



Trans. Amer. Micros. Soc, vol. 23, pp. 191-200. 

 Hamann, O. 1892. Das System der Acanthocephalen. Zool. Anz., vol. 15, pp. 



195-197. 

 LiJHE, M. 1904-1905. Geschichte und Ergebnisse der Echinorhynchen-Forschung 



bis auf Westrumb (1821). Zool. Ann., vol. 1, pp. 139-353. 

 1911. Acanthocephalen. Die Siisswasserfauna Deutschlands, Heft 16. Jena, 

 Porta, A. 1905. Gli Echinorinchi dei Pesci. Arch. Zoologico, vol. 2, pp. 149-214. 

 Van Cleave, H. .T. 1913. The genus Neorhynchus in North America. Zool. Anz., 



vol. 43, pp. 177-190. 



1916. Filicollis botulus n. sp., with notes on the characteristics of the 



genus. Trans. Amer. Micros. Soc, vol. 35, pp. 131-134. 



1916a. Acanthocephala of the genera Centrorhyuchus and Mediorhynchus 



(new genus) from North American birds. Trans. Amer. Micros. Soc, vol. 



35, pp. 221-232. 



1918. Acanthocephala of North American Birds. Trans. Amer. Micros. 

 Soc, vol. 37, pp. 19-48. 



1918a. Acanthocephala of the subfamily Rhadinorhynchinae from American 

 fish. Jour. Parasitol., vol. 5, pp. 17-24. 



1919. Acanthocephala from the Illinois River, with descriptions of species 

 and a synopsis of the family Neoechinorhynchidae. Bull. 111. Nat. Hist, Sur- 

 vey, vol. 13, Art. 8, pp. 225-257. 



