38 F5ULLETIN 41, UNITKD S'JWTES NATIONAL MUSEUM. 



185H. GiRAKi>, ('hakles — Coutiniud. 



cxtcmling from Pugot Sound anil (Im Britisli jiossussioiiH at tlic north lo tlio valleys ot' the 

 Rio Gila and Rio (Trandc del \orte (Rio Bravo) to the .south, and even including the Mexican 

 provinces of Tainaulipa.s,Xew Leon, Coahuila, Chihuahua, and Sonora. 



The investigations of such an amount of material could not be extemporized. Indeed, 

 even investigations upon these various collections could not have been traced each separately 

 in the order in which they were collected. From a preliminary examination of the first lot 

 received in 1851 I became vei'y soon impi'essed with the difficulty of the task and foresaw the 

 utter impossibility, at that time, to do anything like Justice to the subject. 



In the mean time, however, a Notice upon a collection of finhen from the southern bend of the 

 TenncKgee Biver, in the ,State of Alabama, by Louin Ayassiz, was published, "■' containing several 

 members of the (\yi)rinoid family. And some time afterwards appeared a Synopsii of the 

 Iclithifoloyical Faima of the Paeifie slope of North America, chiefly from the collections made 

 l)y the V. S. ExiAoring Expedition under the eominand of Cai)t. ('. Wilkes, luith recent additions 

 and comparisons with eastern types. By the same author. \ 



These two papers, though anticipating .some of the following results, were greeted with a 

 hearty weU'onu',. and I can only regret tliat the second was not concluded up to the time I am 

 writing. I have delayed entering into tliis sul)ject as long as was consistent with the duties 

 imposed upon me. 



In both of them we tind the laudable desire, of attenii)ting to bring back into use the long- 

 forgotten genera of Rattuesquit. which fell into disuse becau.se of their own imperfection, 

 and if they have not passed into the <()mui(pn nomenclature of the day it was owing to their 

 defect more than to the partiality of naturalists ; for we may well imagine how anyone 

 would feel when rebuilding another's work, as little known to the author as to the com- 

 mentators them.selves. 



And yet, for my part. I havi' always looked upon the restoration of Rafinesque's genera 

 and species as highly desirable, as soon as they h4id once been proposed and introduced into 

 science as names. But in order to do justice to the scheme, it was necessary to the under- 

 taking that (uie should go to the very ground covered by Rafinesqne himself during all sea- 

 sons of the year, to enable us to di.scriminate between that which Rafine.sque really observed 

 and that which is imaginary. 



That the Ichlhyologia Ohiensis has been and still is a stumbling block, is fully evinced by 

 the fact that Dr. J. P. Kirtland. the Ohio ichthyologist, of untiring and energetic zeal and 

 perseverance, was battled in many of liis attempts to determine Rafinesque's genera and 

 species. 



These genera and species, thus restored by Prt)fessor Agassiz, may therefore not be re- 

 ceiv^ed by all ichthyologists as the final settlement of that much controverted question. But 

 whether the identification be right or wrong, .since we must have these names, I sincerely 

 hope tliey will now be adopted, once for all, as projiosed. 



Since circumstances have compelled me to write this memoir before the completion of 

 Agassiz's synopsis, I have restored the balance of Rafinesque's genera in the family of Cy- 

 prinoids: such are Plargyrus ami iSemotilus. Ouco upon that field of inquiry I reverted to 

 Jlec\ie\' a geneva A rffy reus iuv\ Leucosonui^, and showed their claim for admission upon the 

 .same general principles and canons of scientific nomenclature. 



On a former occasion the genus Leucosomus Vfa,s altogether misunderstood by nu>, and it 

 it thus entered into the "History of the Fishes of Massachusetts, by Dr. D. H. Storer." 

 Professor Agassiz was led into the same error.; Meckel, by inadvertence, applies the name 

 of Cyprinus chrysoleucus, Mitch., to Leuciscus pulchelhis, Storer, as shown by the figures 

 given of its teeth and the wording of its generical diagnosis. Leucosomus, therefore, is 

 identical with Cheilonemus, and accordingly the name is to be adopted. Cheilonemus was 

 proposed for Leuciscus pulchcllus, and allied species, when it was sui>i»osed that Leuciscus 

 chrysoleucus would constitute the type of the genus Leucosomus. But it is now well 

 ascertained that Leucisc^is chrysoleucus of Mitchell belongs to Rafines(iue's genus Liixilus; 

 and Lvxilus has the priority over Leucosomus. 



Leuciscus (iracilis of Richardson, referred by Heckel to Leticosomus. is of a difterent generic 

 type. 



As to the genus Aryyreti.s, Heckel includes iu it two sjiec ies generally distinct, ('ypriiuis 

 atronasas, Mitch,, and Oypr. rubripinnis. Mus. Par. MS. But Cyprinus rtibripinnis is iden- 

 tical with Leuciscus cornut^cs, and since Leuciscus cornutus is to enter the genus Plargyrus of 

 Rafinesiiue, C(/prinM» a«rowa»MS remains as the type of the genus Argyreus, which again is 

 identical with Jthinichthys. It must be recollected, however, that the teeth figured by 

 Heckel under the name of Argyreus rubripinnis are those of Plargyrus cornutus. 



' Am. Jour, of Sci., 2d .ser. xvii, 1854, pp. 297, 3.53. 

 f Am. Jour, of Sci.. 2d ser.. xix. 18.55, ]ip. 71. 215. 

 ; Amer. Jour, of Sci.. 2d ser., xix. 1855, p. 225. 



i 



