524 Memoir Sears Foundation for Marine Research 



the claspers are bifid or trifid, (b) whether the caudal filament is long or short, and (c) 

 whether the upper margin of the second dorsal is nearly straight or is so deeply concave 

 that the fin is partially or wholly subdivided. However, it is not possible to draw any sharp 

 line between those in which the caudal filament is long and those in which it is short, 

 or between those in which the second dorsal is straight or slightly concave, or deeply 

 concave or subdivided. The nature of the claspers is not a satisfactory character for 

 generic diagnosis, for it is not known for all species, and in any case it would apply to 

 the male sex only. Therefore, we include all of the members of the family that lack an 

 anal fin under the generic name that was earliest applied to any of them, i. e., Hydrolagus 

 Gill 1862. 



Key to Genera 



I a. With a separate anal fin, sharply marked off from the caudal fin by a deep notch. 



Chimaera Linnaeus 1758, p. 524. 

 lb. Without a separate anal fin. Hydrolagus Gill 1862, p. 533. 



Genus Chimaera Linnaeus 1758 



Chimaera Linnaeus, Syst. Nat., j, 1758: 236; type species, C monstrosa Linnaeus, Atlantic, designated by Jordan 

 and Gilbert (Bull. U. S. nat. Mus., 16, 1883: 54). 



Generic Synonyms:*" 



Chimera Rafinesque, An. Nature, 181 5 : 92; emended spelling for Chimaera Linnaeus 1758, by ref. to Linnaeus. 

 Ckimaira Dumeril, Mem. Acad. Sci. France, 27 (i), 1856: 155; emended spelling for Chimaera Linnaeus 

 1758, by ref. to Linnaeus. 



Doubtful Synonyms: 



Callorynchus Gronovius, Acta Helvet., 7, 1772 : 49; type and only described species, C. atlanticus Gronovius;" 



C.centrina also included by ref.; Gray, Cat. Fish. Coll. and Descr. by L. T. Gronow, in Brit. Mus., 



1854: 16, for C. atlanticus Gronovius and C.centrina Gronovius. 

 Not Callorynchus Gronovius, Mus. Ichthyol., I, 1754: 59, pi. 4; Cuvier, Regne Anim., 2, 1817: 140; and 



many subsequent authors; see discussion, p. 560, ftn. 121. 

 Not Chimaera Poli, Testacea . . . Sicil., I, 1791 : 31; for bivalve mollusks. 

 Not Chimaera Ochsenheimer, Schmetterlinge Europ., 2, 1808: i; for insects (Lepidoptera). 

 Not Chimaera Hitchcock, Ichthyol. New Eng., 1858: 118; for a reptilian fossil footprint. 



Generic Characters. Chimaeridae with anal fin separated from caudal by a deep 

 notch. Dorsal spine attached to anterior margin of first dorsal along basal V3-V2, then 

 free; its free portion grooved along posterior side and with a more or less prominent 

 row of pointed teeth directed toward the base along either margin of the groove. Second 

 dorsal fin not partially subdivided, its upper margin straight or only weakly concave, 

 much lower than first dorsal ; connected with first dorsal by a low fold of skin without 

 rays; its rear termination close to origin of caudal. Caudal fin lancet-shaped, about as 



40. Fowler (Bull. U. S. nat. Mus., loo [jj], 1941: 487) includes the fossil genera Plethodus Dixon 1850 (Fossils of Sus- 

 sex, 1850: 366) and Dipristis Gervais 1869 (Zool. Pal. Gen., 1869: 240) among the synonyms of the modern genus 

 Chimaera. 



41. Gronovius' description of his C. atlanticus fits well in the genus Chimaera except for his statement that there was no 

 anal fin; but the latter is so inconspicuous that it may have been overlooked. 



