FISHES 99. Five-bearded Rockling. Motella mustela, Linn. Common. 100. Four-bearded Rockling. Motella cim- bria, Linn. Cocks has recorded it from Falmouth. Mr. Cornish states that it is small and rare in Cornwall. Holt mentions a specimen taken from the stomach of a hake trawled in or off the Bristol Channel. It was 8J inches long, and the first ray of the dorsal fin was over 2 inches in length (Journ. M.B.A. v. 343). 101. Three-bearded Rockling. Motella tri- cirrata, Bl. Very common. There are three principal stages in the life history of this fish. In the first stage they are silvery little fish with long pectoral fins which are black at the ends. These are known as mackerel midges and swim at the surface in June. The older fish up to a length of about 6 inches are of a uniform dark colour and are found under stones between tide marks. The adults, which reach a length of 20 inches and are spotted, are found in deeper water. O2. Lesser Fork-beard. Raniceps raninus, Linn. Mr. Dunn has obtained it at Mevagissey, and Mr. Cornish recorded it several times from Mount's Bay from 1863 to 1878. 103. Bearded Ophidium. Ophidium barbatum, Linn. A specimen 10 inches in length from Pad- stow is in the British Museum. PLEURONECTOIDEI 104. Halibut. Hippoglossus vulgaris, Flem. This fish is very seldom caught on the Cornish coast, but a few specimens have been recorded. One weighing 102 Ib. was obtained at Mevagissey in 1870, and another weighing about a hundredweight was taken on a spiller in Mount's Bay in 1882 (Cornish, Zoologist). 105. Long Rough Dab. Hippoglossoides limandoides, Bl. Cocks obtained a specimen at Falmouth. 1 06. Turbot. Rhombus maximus, Linn. Common, and reaches a large size. The young up to a length of I inch or i^ inches and in process of metamorphosis swim at the surface, and are often to be seen in harbours in May or June, e.g. Mevagissey. 107. Brill. Rhombus Itevis, Gottsche. Common, taken by trawlers. The young are similar to those of the turbot, but smaller, and are found in similar conditions. 1 08. Common Topknot. Zeugopterus puncta- tus, Bl. ; Rhombus punctatus, GUnther. Rather common, but not abundant. Day obtained it at Penzance in i88i,and Cornish stated in the Zoologist that he obtained forty- eight specimens between 1858 and 1866. 1 09. One-spotted Topknot. Zeugopterus uni- macu/atus, Risso. J. Couch alludes to a specimen from the Bristol Channel in 1863, and Cornish ob- tained one in 1880. It is evidently rarer than the common topknot. 1 1 0. Norway Topknot. Zeugopterus norwegi- cus, Gdnther. Four specimens trawled in July 1891 be- tween the Eddystone and Rame Head in 25 fathoms. One specimen trawled six miles from Plymouth Breakwater in March 1892. The last specimen was a ripe female. It does not exceed 4 inches in length. in. Sail Fluke or Megrim. Lepidorhombus megastoma, Donov. Common on the trawling grounds. The sail-fluke and carter of J. Couch's British Fishes are the same species, but it is usually called the megrim in the fish trade. The legend of its floating to the shore in the Orkneys with its tail erected as a sail seems to be founded on fact, as it seems to come to the surface and be thrown ashore there in storms. Arnoglo: 112. Scald-fish or Scald-back. laterna, Walb. Very common on sandy ground, the young in shallow water, the adults on the trawling grounds. The A. lophotes of Gunther, dis- tinguished by the elongation of the anterior rays of the dorsal fin and of the rays of the pelvic fins, is the adult male. 113. Broad Scald -fish. Arnoglossus groh- manni, Bonap. Two females trawled by Holt in Gerran's Bay, July 1897, both full of spawn. 114. Plaice. Pleuronectes platessa, Linn. Abundant, but not so large as those of the northern part of the North Sea. There are several local races of plaice differing not only in size at maturity, but in minute structural characters ; the English Channel race ex- tends to the coasts of Holland, further north is a larger race, while the Iceland plaice and Baltic plaice are quite distinct. 301
