DETERMINATION OF GENERIC TYPES, ETC. 45 



It can hardly be advanced against this view that Dujardin's Doch- 

 mius is essentially different from Uncinaria. Aside from crinifortnis 

 [melis as synonym] and trigonocephalus [vulpis as synonym] of Du jar- 

 din, he included in this genus D. ursi which he gave as doubtfully dis- 

 tinct species, and as possibly identical with his trigonocephalus/ cras- 

 sus, of which he examined only the female; and tuo&formis Zeder, for 

 which he gave a description based upon his own study, but not contain- 

 ing any striking characters which would lead us to assume that it was 

 because of this species that he rejected the name Uncinaria. 



It was because of the inclusion of metis and vulpis in Dochmius that 

 in 1899 (p. 164) we took vulpis as "type by inclusion" for Dochmius. 

 For our reaspns for taking vulpis as type of Uncinaria, see page 54. 



Fissula Lamarck, 1801, 339, contained two species, namely, intesti- 

 nalis (Bloch) and cystidicola; cystidicola (farionis) was the type of 

 an earlier monotypical genus. 



Helicothrix Osman Galeb, 1878b, was proposed with four species: 

 spirotheca, upon which two monotypical generic names (Pseudonymus, 

 1857, and Ptychocephalus, 1861) had already been based; hydrophili; 

 hydroi; and hydrobii. 



Ophiostoma Rudolphi, 1801, was proposed with the species phocse, 

 globicola, rajse, and farionis (Cystidicola} as positive and with bifida 

 as probable member of the genus. In the same paper, Rudolphi (p. 

 62) declared in favor of priority in selecting generic names, but (p. 64) 

 objected to names like Cystidicola based upon the habitat. Ophios- 

 toma, accordingly, appears to be a clear case of renaming the earlier 

 genus, hence should take the same type as the older genus. Later 

 (1809, 124) Rudolphi considers rajas and globicola species dubiae and 

 unites (p. 119) phocse, and bifida under the name dispar, retaining 

 cystidicola as valid species. If now objection is raised to making 

 cystidicola "type by inclusion" of Ophiostoma, the only other ruling 

 would be to select phocse, (female dispar in Rudolphi, 1809, 119). 

 From the data stated, a ruling on the principle of tj T pe by inclusion 

 seems to be the best method of proceeding. 



Ehabditis Dujardin, 1845a, 239, was proposed with four species: ter- 

 ricola, aceti, tritici, and glutinis (type of Anguillula, 1786). From 

 these species (see p. 134) it is seen that if page precedence were fol- 

 lowed, terricola would be type of JRhabditis, and this ruling would 

 agree with the action taken by Bastian, 1865c, who retained in Ehab- 

 ditis only this one of Dujardin's original species; it would also agree 

 with Railliet, 1893a. Diesing, 1851a, the first reviser after Dujardin, 

 eliminated all of Dujardin's original species to other genera, thus totally 

 suppressing Rhabditis. Gervais & van Beneden, 1859b, the next 

 authors we have examined, mention by name only aceti as member of 

 Ehabditis, transferring tritici to Anguillulina. If the principle of the 

 "first reviser" after Diesing were followed, it would be questionable in 

 the minds of some authors whether aceti could be designated as type 



