228 ACANTHOPTEBYGII. 



Family, XXY— MUGILID^, Owner. 



Branchiostegals from five to six: pseudobranchisB present. Gill-openings wide: 

 gills four. Form of body oblong, compressed, while the head and anterior portion 

 may be depressed. Eyes lateral, with or without adipose lids. Mouth narrow, 

 or of moderate width. Opercles usually unarmed. Teeth very fine, sometimes 

 absent. Two dorsal fins, separated by some interspace from each other, the first 

 consisting of four stiff spines ; anal slightly longer than the second dorsal ; 

 ventral abdominal, and suspended from an elongated shoulder bone, it consists 

 of one spine and five rays. Scales cycloid, rarely ctenoid, extending on to the 

 head. Lateral-line absent. Pyloric appendages generally few. Air-bladder 

 large. Vertebra? 24 to 26. 



In India and Burma I have observed that in such forms as Mugil corsula, 

 M. cascasia, and M. Hamiltonii, which mostly or entirely reside in fresh water, 

 the scales are strongly ctenoid, while the two last have merely two pyloric 

 appendages. 



Geographical distribution. — These cosmopolitan fishes are found in most tem- 

 perate and tropical seas, where they frequent the shores, and ascend the larger 

 rivers even into fresh water. Some forms appear to be entirely restricted to 

 fresh water. 



Genus I. — Mugil, Artedi. 



Branchiostegals from four to six : pseudobranchioi present. Eyes with or without 

 adipose lids. Mouth more or less transverse, having a shallow cleft, and the 

 anterior edge of the mandible sharp. Teeth, when present, minute, pyloric appen- 

 dages generalhj few (2-10). Upper portion of the stomach very muscular : intestinal 

 tract long. 



Fishes of this genus may be divided for convenience into (1) such as possess 

 or (2) are deficient in adipose eye-lids. The second dorsal fin may commence 

 opposite, anterior, or posterior to the origin of the anal ; while an elongated 

 axillary scale may be present or absent, and the soft dorsal and anal fins may 

 be scaled or scaleless. The lips may be thin or thickened, and provided with 

 papillae, which would seem to be more prominent at some seasons than they are 

 at others. Usually these fishes have eight or nine branched rays to the anal fin, 

 the last, which is divided to its base, being considered as one. But in some 

 species, as the Indian M. parsia, or the British M. capito, either number may 

 be found. 



Respecting the mullets which live in the British seas, some differences of opinion 

 exist. Irrespective of M. curtus, Yarrell : Thompson and Couch merely recog- 

 nized two, Mugil capito, a " thin-lipped " species, and M. chelo, a " thick-lipped." 

 Dr. Giinther has widely diverged from the opinions of his predecessors, and 

 states that the following all belong to the British Fauna, Mugil octo-radiatus, 

 Giinther ; M. , capito, Cuvier ; M. auratus, Basso ; M. septentrionalis, Giinther, 

 while he discards M. chelo altogether. Couch observed that he was only 

 acquainted with two, to which he restricted his history and description ; so merely 

 copied M. auratus and M. octo-radiatus from the " catalogue of fishes," and entirely 

 omitted M. septentrionalis. As far as my experience goes, it agrees with Yarrell, 

 Thompson, Couch, Steindachner, Moreau, and others ; M. octo-radiatus, Giinther, 

 being simply a synonym for M. capito whenever the anal fin has eight instead of 

 nine soft rays: and M. septentrionalis, Giinther, being identical with M. chelo; 



