910 



SCAXniXAVIAX FISHE.- 



llerriii'i'-shoals. and ilrvuurs theii' I'oc. Afterwards it 

 returns to deeper water, and does Tiot re-appear until 

 the close of summer, at the end of September. lixcept 

 during the spawning-season the Gwyniad is so cunning 

 and cautious a lisli that its sagacity lias given rise to 

 a pi'overbial exiiression, a slv person being called an 

 arfl sik (a thorougli <TW\-niad). It is also timid, and 

 so voracious as to de\our not only the roe of other 

 fishes but also its own. It dies soon after it is taken 

 out of the water." This greatlv dejiends, however, on 

 tiie depth at which it is caught. When drawn up from 

 very deep water, it dies at once, the air-bladder swells, 

 and the belly is distended, sometinies to monstrous 

 dimensions. 



The lake Gwyniads also assemble in shoals twice 

 a year. The first period is during suuuner, when in- 

 sect life is most thriving, gnats and dragonfiies sport 

 at the SiU-face or drcjp into the watei-, and when tlie 

 small crustaceans {Entomostrnca and fresh-water Gam- 

 maroids) are most plentiful. Shoals of Gwyniads then 

 seek their food at the surface and in the shall(n\'s. 

 The other period is in autunui and winter, when the 

 Gwyniads gather to spawn. Similar oljservations have 

 been made in North America". In Lake Ontario, for 

 instance, the Gwyniad is taken early in spring far out 

 in the lake, in about '200 feet of water. At the be- 

 ginning of June it repairs in siioals to the coast in 

 quest of food. At the Iteginning of August, when the 

 heat of the upper layers of water is too oppressi\e, it 

 speedily retires to the deeper and cooler parts of the 

 lake, .\bout the middle of (Jctober it again approaches 

 the coast, but on this occasion in order to spawn, an 

 operation which lasts from the middle of November 

 to the beginning of December, and is performed in 

 water of a temperature of about 40° Fahr. (+ 4^/3 C). 

 15ut in certain lakes the summer shoals do not ajjpeai', 

 for example in Lake Erie, according to Milnee, where 

 the surface temperature sometimes rises to 75^ Fahr. 

 (+ 24° C), and wdiere the Gwyniad resoi-ts in summer 

 to the deepest ])arts of the lake. Here, howevei-. it is 

 1)}' no means condemned to starvation. 



The lai'gest and most developed Gwyniad forms, 

 with their more or less ventral mouth (situated on the 

 under surface of the snout), are evidently in the first 

 place bottom-feeders. Thej' seize the larger Ganuua- 

 roids and the mollusks {Limnaa, PJanorJilx, risidium, 

 etc.) which live among plants and in the mud, not to 

 mention, as we have already stated, that thev are vora- 

 cious roe-eaters. Small iry also enter into their diet. 

 Young (Twyniads and the smaller forms, with their 

 more terminal mouth (situated at the tip of tlie snout), 

 are in general shore and surface fishes, and have to 

 content themselves with smaller prey. But in many 

 Scandinavian lakes, especially in Norrland and La|iland, 

 small crustaceans (Enfnmosfrara) and gnat-wcjrms occur 

 in such multitudes that even the large Gwyniads grow 

 fat on them. 



The spawning-season occurs, as we have mentioned, 

 in autumn and winter'', as a I'ule from the middle of 

 October until after the beginning of Januar\-. The 

 young spawn in comparatively shallow water, onh 1 — ?. 

 fathoms in depth, and earliest in the year; oldrr spe- 

 cimens generally breed later and in the deeper ])arts 

 of the lakes. The males usuallv come tii'st to the 

 spawning-place, the females following them. The breed- 

 ing fishes display eager excitement, especially at night. 

 The males even cling fast with their teeth to the fe- 

 males, seizing them under the gills or by the pectoral 

 tins. Or the pair — sometimes two or more males and 

 one female — pressed close together, run in sinuous 

 curves towards the surface or even aljove it, "Ijelh' to 

 belh', \\ith tlieir sides glenniing bright in the water, 

 where they strive and wriggle until they are rid of the 

 roe and milt, which adheres to the bottom, and on 

 stones or nets" (Gisler). In stormy, snowy, or very 

 cold weather the spawning is jjcrformed in the same 

 way, but several metres l)elow the surface. The water 

 round about is dyed with loose scales, and after the 

 spawning the exhausted fish seek out resting-places. 



The eggs are light yellow, and their dimensions 

 vary considerably, according to the size of the mother 

 fish. In hlasikar from Lake Ring the ripe eggs measure 



" See Mr. P. Kiel in Br. Goode, Fisher., Fisher. Industr. U. 6'.. sect. I, p. .510. 



' .\ccording to Brehm's description of the fishery in the R. Obi, tlje Gwyniuils iisceiid the river from tlie sea ulieii the ice Ijieaks iiji. 

 spawn at the end of the summer, and return in August, usually at tlie end of the uiunth. to the Arctic Ocean, or n1 least to the Gulf of 

 Obi (Thierlehen, Bd. VIII, p. 235). The Gwyniads brought home by Theel and Trydoji from the Yenisei in 1876 also show (see Smiii. 

 Miksm. iSalmo7i., tab. metr. XIII, No. 424, celt.) that the e,5gs were so large at the beginning of July that the spawning might well have 

 been performed in the course of the summer. In some of the very deep Swiss lakes too. according to F.vno, the Gwyniad spawns in .July 

 and August. 



