44 . BUREAU OF ANIMAL INDUSTRY. 



identical genera, one of which has a natural type, we see no possible 

 objection to ruling that ornata is type of Nematoxys by inclusion. 

 For the possibility of designating commutata as type, see under 

 Sclerostoma, page 44. 



Sclerostoma Rudolphi, 1809, was a subdivision of Strongylus, containing two species 

 of Strongylus, namely: 



equinus, which is type of the monotypical genus Strongylus, and, if page pre- 

 cedence were followed, type of Sclerostoma. 



dentatus, which was transferred to (Esophagostomum by Molin, 1861, where it 

 has since remained and of which we have in this paper designated it as type. 



According to the present status, equinus might be type of 

 toma either by page precedence or by elimination, and the principle 

 of type by inclusion gives the same result. 



In the case of Nematoxys, cited above, some authors might be inclined 

 to argue that since ornata is type of Cosmocerca, commutata should be 

 taken as type of Nematoxys. If this same argument were applied to 

 Sclerostoma, and dentatus made its type, then the present (Esophagos- 

 tomum would have to be revised, since (E. dentatum would be type of 

 an earlier genus. It is thus seen that the principle of type by inclu- 

 sion settles the case in a less complicated manner. 



Spirura Diesing, 1861a, contains all of the original species (and no 

 other) of Spironoura; it is distinctly a deliberate renaming of Spiro- 

 noura, and the two genera being absolutely identical it can work no 

 hardship to rule that whatever type is selected for Spironoura should 

 also serve as type of Spirura. If page precedence were followed, 

 gracile would be type in both cases. If Spirura is interpreted as an 

 emendation of Spironoura, no question can arise against selecting the 

 same species as type of both genera. 



We now come to several still more complicated cases: 



Cheiracanthus Diesing, 1838, 1839, contained two species: 



robustus Diesing, for which Diesing gave Gnathostoma hispidum as probable syn- 

 onym ( Gnathostoma is monotypical ) . 

 gracilis Diesing. 



In this case Diesing knew that he was renaming an earlier mono- 

 typical genus; considering robustus and hispidwm as probably identical 

 specifically, he had no grounds for considering that Cheiracanthus was 

 not congeneric with Gnathostoma. Page precedence, if followed, 

 would make robustus type of Cheiracanthus. To rule that robustus is 

 type by inclusion seems more satisfactory, since it sets a stamp of dis- 

 approval upon such unjustified renaming of preexisting genera. 



Dochmius Dujardin, 184:5a, represents a case somewhat similar to 

 Dispharagus. Dujardin was well aware of the existence of Uhcinaria, 

 1789, with two species, metis and vulpis, both of which he included in 

 Dochmius. Dujardin's proposition of a new name was therefore a 

 deliberate renaming of an earlier genus. 



