390 Dr. A. Giinther on the History of Echeneis. 



Agassiz and Joh. Miiller to remove it from that order. Agassiz*, 

 although he does not mention either Voigt or Blainville, explains 

 the nature of the disk exactly in the same manner, and places 

 the genus in the family of Scombridse. Miillerf also does not 

 appear to have been acquainted with the opinion of Voigt, and 

 draws his conclusion merely from the structure and the inser- 

 tion of the ventral fins, so widely different from those in the 

 Malacopterygii jugulares : he establishes for the genus a sepa- 

 rate group (Echeneidse) in the family of Gobioidei. The close 

 affinity of Echeneis with Elacate was first recognized by Hol- 

 brookj; and if Echeneis be placed among the Scombridfe or 

 Gobioidei, Elacate must follow. 



III. Discrimination of the Species. 



The progress of our knowledge of the different species will 

 be more easily surveyed if we divide the account according to 

 the species themselves. Although, as we have seen, the two 

 most common species were known to ante-Linnsean authors, 

 they were confounded together ; and even Willughby and Artedi 

 believed that there was one species only. Linnseus (Syst. Nat. 

 i. p. 446 §) first distinguished Echeneis remora and Echeneis 

 naucrates, characterizing the one as " E. cauda bifurca, striis 

 capitis octodecim,^^ and the other as "E. cauda Integra, striis 

 capitis viginti quatuor," — diagnoses by which later ichthyologists 

 were led into great errors, the form of the caudal fin being con- 

 sidered as a constant specific character. 



1. Echeneis remora. 



We shall not commit any great error if we refer to this spe- 

 cies, which is the most common in the Mediterranean, the more 

 or less philosophical accounts of Ovid, Pliny, Plutarch ||, iElian, 

 Oppian, AYotton, and Ilondelet. The first rough figures which 

 without any doubt represent the present species, were given 

 by Nieuhoff, /. c, and four years afterwards by Willughby, 

 with the name oi Remora Imperati (Appendix, p. 5, tab. 9. f. 3), — 

 the figures of Valentyn (iii. f. 32, p. 357. n. 32) and Kenard 

 (i. tab. 1. f. 3) being very bad, and scarcely distinguishable. 



Klein and Gronovius distinguish the same species as Linnaeus. 

 Whilst the former indicates several varieties of the large Indian 



* Recherch. Poiss. Foss. v. p. 117 (tab. G represents the skeleton of 

 E. naucrates). 



t Berlin. Abhandl. 1844, pp. 158, 15!). 



X Iclithyol. South Carol, p. 104. 



§ And in Amoen. Acad. i. p. 320 ; Mus. Reg. Ad. Frid. i. p. 75. 



II Sympos. lib. ii. and in Vita Antouii. 



