278 SCOMBRESOCIDiE. 



Exocoetus, Halocyp8elus ei Cypselurus, Weinland, Proc. Bost. Soc. Nat. 



Hist. vi. 1859, p. 385. 

 Parexocoetus, Cypselurus et Exocoetus, Bleek, Nederl. Tydschr. DierJc, 



iii. p. 105. 



Jaws short, intermaxillaries and maxillaries separate. Teeth 

 minute, rudimental, and apparently sometimes absent. Body mode- 

 rately oblong, covered, with rather large scales. Pectorals very long, 

 an organ of flying: all the dorsal and anal rays connected by a 

 membrane. Gill-openings very Avadc. Intestinal tract simple, 

 without pyloric appendages. Air-bladder large. 



Pelagic fishes, numerous between the tropics, but extending far 

 into the temperate zones. 



Some of the fishes of this genus arc pro\idcd with mandibulary 

 barbels, which character has been thought of sufficient importance 

 for the creation of a distinct genus, Cypselurus. The reasons why 

 we hesitate to adopt this genus in the form proposed, are, first, be- 

 cause singularly enough these bearded Exocoeti are of small, and 

 frequently of very small size, in fact, young individuals ; secondly, 

 because there is evidence to show that the barbels (which, besides, 

 are of a very soft structure) are frequently mutilated, variable in 

 form, and so often lost that one may well suspect that, in some 

 species at least, they are peculiar to the young state only; and 

 thirdly, because there are the same differentiations of form among 

 the bearded Flying Fish as among the beardless ones. In both 

 groups we find species with long and short ventrals and pectorals ; 

 in both, species with elevated dorsal fin. Therefore we prefer to 

 use for a primary division of the species those characters which we 

 have found to be independent of age. 



I. Ventral fins shortened, not extending to the anal. 



A. Pectoral fins shortened, not more than half as long as the body 



(without caudal). 



1. Dorsal fin of moderate height. 



«. Mandible with a cutaneous appendage, p. 279. 

 h. Barbels none, p. 280. 



2. Dorsal fin elevated. 



a. ]\Iandible with a cutaneous appendage, p. 280. 



b. Barbels none, p. 281. 



B. Pectoral fins long, more than half as long as the body, p. 282. 



II. Ventral fins of moderate length, extending to the origin of the anal, 



p. 284. 



III. Ventral fins long, extending beyond the origin of the anal. 



A. Mandible with a cutaneous appendage. 



1. Pectoral fins shortened, not more than half as long as the 



body (without caudal), p. 284. 



2. Pectoral fins long, more than lialf as long as the body (with- 



out caudal), p. 285. 



