470 SOME QUESTIONS OF NOMENCLATURE. 



well as Astracanthus and Aster acanthus; and among words sufficiently 

 different are Polyodon, Polyodonta, and Polyodontes. 



When rules are once relaxed in this indefinite manner the way is 

 at once open to differences of opinion as to what are to be considered 

 identical or too much alike. Fiseheria and Fisheria appear to me to be 

 sufficiently distinct, and would be so considered by some who think 

 that Polyodon, Polyodonta, and Polyodontes are too nearly alike. While 

 the last three are conceded to be sufficiently distinct by the German 

 Zoological Society, analogous forms, as Heterodon and Heterodontus, 

 are claimed by some zoologists to be too similar, and consequently the 

 latter prior and distinctive name of the "Port Jackson shark" is sac- 

 rificed in favor of the later and inapt Cestracion — a name originally 

 coined and appropriate for the hammer-headed sharks, but misapplied 

 to the Australian shark. 



I agree with those who think that even a difference of a single letter 

 in most cases is sufficient to entitle two or more generic names so dif- 

 fering to stand. The chemist has found snch a difference not only 

 ample but most convenient to designate the valency of different com- 

 pounds, as ferricyanogen and ferrocyanogeu. I am prepared now to go 

 back on myself in this respect. In 1831 Prince Max of Nieuwied 

 named a bird Seaphorhynchus, and in 1835 Heckel gave the name Scaph- 

 irhynchus to a fish genus. 1 In 1863 I used a new name (Seaphirhyn- 

 clwps) for the acipenseroid genus, and that name was adopted by other 

 naturalists. Jordan later considered the literal differences between 

 the avine and piscine generic names to be sufficient for both. I yield 

 the point, and abandon my name Scaphirhynchops. But those who 

 hold to the rule in question will retain it. 



Another set of cases exhibiting diversity of opinion may be exempli- 

 fied. 



In 1832 Eeiuhardt gave the name Triglops to one cottoid genus, and 

 in 1851 Girard named another Triglopsis, Girard apparently not know- 

 ing of Reinhardt's genus. In 1860 the later name was replaced by 

 Ptyonotus. All American naturalists have repudiated the last name. 



In 1854 Girard named a genus of Atlierinids Atherinopsis, and in 

 1876 Steindachner, knowing well the name of Girard, deliberately 

 called a related genus Atherinops. No one, as yet, has questioned the 

 availability of the later name, but one who refuses to adopt Triglopsis 

 because of the earlier Triglops must substitute another name for Ather- 

 inops. 



Who shall decide in such cases, and what shall be the standard? 



1 In lieu of explanations of the etymology, it may be assumed that Scaphirhynchus 

 was derived from 6Ha*l>£ia, a digging or hoeing, and that Seaphorhynchus is from 

 dxccfios, anything hollowed, as a boat. Both Seaphorhynchus and ScapMrhynchus 

 were derived from l 6ua^y], scapha; pvyxos, rostrum' hy Agassi/, in hisNomenclator 

 Zoologicus, but the characters of the respective genera would be better expressed by 

 the etymologies here, suggested, the bird genus having a bill like an inverted hoat 

 and the fish genus a snout like a spade, as the popular name — shovel-billed sturgeon — 

 implies. 



