164 ACANTHOPTERYGIL 



Gdbius jozo, Bloch, t. cvii, f . 3. 



Gobius fuliginosus, McCoy, Ann. and Mag. Nat. Hist. 1841, vi, p. 403. 

 Gobius Britannicus, Thompson, Proc. Zool. Soc. 1837, p. 61, and Nat. Hist. 

 Ireland, iv, p. 111. 



? Gobius paganellus, Moreau, 1. c. ii, p. 225. 



Bock Goby, Couch, Fish. Brit. Isles, ii, p. 153, pi. xcviii. 



B. v, D. 6 | -fa-lip p - 18, V. 1/5, A. T ^L TW , C. 13, L. 1. 39-41, L. tr. 12-13. 



Length of head 4 J to 4|, of caudal fin 5j to 5|, height of body 6 to 6£ in the 

 total length. Fye — prominent during life, diameter 3-| to 4 in the length of the 

 head, 3/4 to 1 diameter from the end of the snout, and separated by a very narrow 

 interspace. Head rather broader than high, snout obtuse. Cleft of mouth 

 moderately oblique, the jaws anteriorly being of nearly equal length, the maxilla 

 reaching to beneath the anterior' edge of the orbit, a deep sulcus goes from the 

 base of the first dorsal fin to the occiput. Several short rows of warts descend 

 from the orbit over the opercles, there are likewise occasionally some similar but 

 horizontal rows, the most visible of which commences at the angle of the mouth. 

 Teeth — several rows of pointed ones in either jaw, the outer of which are larger 

 and more curved than the remainder. Fins — dorsal fins placed close together, 

 but their bases do not quite join, the spines of the first dorsal weak, elongated, 

 and as high as or higher than the body : second dorsal about as high as the 

 body, with its last ray divided to its base. Pectoral, usually a few of its upper 

 rays silk-like, it reaches to above or even behind the anal papilla. The ventrals 

 as a rule extend to the anus. Caudal wedge-shaped, its central rays being the 

 longest. Scales — angular in their exposed portion and ctenoid : 12 or 13 rows 

 between the origins of the second dorsal and anal fins, anterior to the first 

 dorsal fin they are very small and rounded, but continued as far forward as 

 opposite the hind margin of the orbit. None on the cheeks or gill-covers. 

 Colours — subject to considerable variation, being more or less of a dull 

 brown, having a wide but badly marked lateral band, and various blotches or 

 marblings. The fins in the young are light, covered with black spots, except 

 the ventrals which are unspotted : whereas in adults the spots become more 

 expanded, and light sinuous lines are frequently seen on the dorsals, while a 

 black spot usually exists between the two first dorsal spines. In adults the 

 ventrals may be either light coloured or dark with a light outer edge. A black 

 spot is frequently present at the upper portion of the base of the pectoral fin : 

 caudal barred in spots. 



Varieties. — Nilsson states that the pectoral and ventral fins are shorter in the 

 female than in the male, and the two dorsal fins somewhat farther asunder. 

 There is a British example in the National Museum having the outer row of 

 teeth in the upper jaw slightly enlarged, and which it has been suggested may 

 be identical with Gobius auratus, Risso. Moreau, gives the number of lateral 

 transverse rows of scales at 15 to 16. 



Names. — Sea-gudgeon and rock-fish, due to their living in rocky localities or 

 attaching themselves to rocks by means of their ventral fins, a faculty denied to 

 them by Fleming. Groundling, Cornish observes that in Cornwall it is some- 

 times termed Miller's thumb (see pp. 46, 48, ante). Cabot, French. 



Habits. — Resides in the neighbourhood of rocks, and Couch has observed that 

 having carried off its prey in its mouth, as does the shanny, it subsequently 

 struggles with it. This goby is occasionally found in rock pools situated above 

 the reach of any but very high tides. When detected, it darts away from its 

 place of concealment to some more secure retreat, while its colour aids in 

 preventing its being seen. Its food appears to be small fishes, crustaceans and 

 other animal substances, but ore-weed has also been taken from its stomach. 

 Couch mentions having taken a shanny 2 inches long from the inside of a 

 rock-goby which but little exceeded 6 inches in length. He likewise remarks that 

 this fish is equally capable of living in fresh or salt water,, even if changed 

 suddenly from one to the other. 



Breeding. — About June. 



