DETERMINATION OF GENEEIC TYPES, ETC- 53 



Distoma lanceolatum, for instance, has been designated by several 

 authors as type of Distoma, but such designation can not hold, since 

 Distoma is simply Fasdola renamed, and the type of Fasciola had 

 already been established by elimination; furthermore, lanceolatum was 

 not one of the original species of either Fasciola or Distoma, hence 

 it was not available as type. 



Uncinaria vulpis had been designated as type of Uticinaria, hence 

 Looss's (1902) selection of U. metis as type is not to be accepted * unless 

 he can show that the earlier designation of U. vulpis was inadmissible. 



The view has been advanced by several authors that a writer in order 

 to designate a type for an earlier genus must actually divide the genus. 

 This view has not been generally accepted, nor is it one which can not 

 be nullified at will, for any author can surely propose a typical subgenus 

 and at that time determine the type. 



In some cases the author of a genus has selected the type after the 

 genus has been published. As original authors can best tell what par- 

 ticular species they had in mind in establishing their genera, probably 

 all authors will agree to the following types: 



ROUNDWORM GENERA WITH TYPES BY LATER DESIGNATION. 



Alaimus de Man, 1880 (primitivus designated by de Man). 

 Anthraconema zur Strassen, 1904 (weismanni designated by zur Strassen). 

 Anticoma Bastian, 1865 (eberthi designated by Bastian), see p. 87. 

 Aphelenchus Bastian, 1865 (avenge designated by Bastian), see p. 87. 

 Arseolaimus de Man, 1888 (bioculatus designated by de Man). 

 Axonolaimus de Man, 1889 (spinosus designated by de Man). 

 Cephalobus Bastian, 1865 (persegnis designated by Bastian), see p. 92. 

 Chromadora Bastian, 1865 (vulgaris designated by Bastian), see p. 94. 

 Chromagaster Cobb, 1894 (purpurea designated by Cobb). 

 Comesoma Bastian, 1865 (vulgaris designated by Bastian) , see p. 95. 

 Cyalholaimus Bastian, 1865 (ocellatus designated by Bastian), see p. 97. 

 Oylindrolaimus de Man, 1880 (communis designated by de Man). 

 Gigantorhynchus Hamann, 1892 (echinodiscus designated by Hamann). 

 Hypodontolairnus de Man, 1886 (insequalis designated by de Man). 

 Laxus Cobb, 1894 ( longus designated by Cobb ) . 



lAnhomceus Bastian, 1865 (hirsutus designated by Bastian), see p. 116. 

 Monhystera Bastian, 1865 (stagnalis designated by Bastian), see p. 120. 

 Mononchus Bastian, 1865 (truncatus designated by Bastian), see p. 121. 

 Neoechinorhynchus Hamann, 1905 (clavseceps designated by Hamann). 

 Neorhynchus Hamann, 1892 (clavseceps designated by Hamann). 

 Parachordodes Camerano, 1897 (tolosanus designated by Camerano). 

 Paramermis von Linstow, 1898 (crassa designated by von Linstow). 

 Penzanda de Man, 1889 (velox designated by de Man). 

 Phanoderma Bastian, 1865 (cocksi designated by Bastian), see p. 129. 

 Plectus Bastian, 1865 (parietinus designated by Bastian), see p. 130. 

 Prismatolaimus de Man, 1880 (intermedius designated by de Man). 

 Rhabdolaimus de Man, 1880 (terrestris designated by de Man). 

 Spira Bastian, 1865 (parasitifera designated by Bastian), see p. 137. 



1 Looss also has recently accepted this view. 



