PEUCIl. 



:il 



,u;ating" its species until three oi' f'uur years old". This 

 may be verj' much influenced, however, by tjie abun- 

 dance oi" scal■cit^• ot its food, which consists (j1 small 

 fry, roe, insects and worms. 



The spawning-season \ai'ics according to the depth 

 of the water; in shallow lakes it is often earlier than 

 tlie middle of April, but in deeper water, in Lake Wetter 



but tlien- numlicr \aries considei'aljly ni |)roportion to 

 the size of the lish. In a female weighing about 255 

 gi'annnes Lund estimated the number of the eggs to be 

 26,880, and in another weighing about 584 grammes, 

 ()G,1.")(). in a female 2 lbs. !)' , oz. in weight Bloch' 

 estimated tlie nnndjer of the eggs to I)e 268,800. From 

 these estimates we may imagine how (|nickly the Perch 



and the island-belts for exanipic, not before the middle : might multiply. That it does not do so, may be 



of May, and generally towards the end of that month. ascribed to the fact that tlu; roe is in one mass, and is 



It is also much influenced by the temperature and the i thus more lial)Ie to be devoured by fishes of prey and 



earliness or lateness of the spring. When the spawning- [ waterfowl, or in stoiany weather cast on the shore, 



season has ai-rivcd, or, more correctly, some days before ! where it dries up, etc ll is also proliahlc that it is 



its arri\al, the Perch leaves the deep water where it has inipossihlc for the milt of the mah; to fertilize all the 

 |)asse(l the winter, and, collected in large shoals, wanders 

 to points along the shore where the water is shallow 

 and the bottom consists of stones or sand covered with 



eggs enclosed in the roe-sh(?atli. 



As a general rule, the males seem to be less mime- 

 rous than the females — among twenty ])erch ijought 

 reeds {Arimdo pkragmites), or where it can find sunken ] at the same time in a mai'ket-place in Stockholm, there 

 twigs and branches. If it fails to find any spots of ' were only three males, and all three were among the 



this nature, it deposits its spawn among tufts of rushes 

 {Srirpufi) and horse-tail (E(juisetum). The roe of the 



smallest of the twenty. No external distinction as to 

 sex was visible at this time (in December). The opinion 



Perch is not made up, as is generally the case among j that the female (according to others, the male) has a 

 fishes, of loose grains covered only with a viscid mucus greater depth of body or a smaller head, was not borne 



and easily detached from each other as soon as the roe 

 is deposited, Ijut is enveloped in a netty membrane 

 which holds the grains more closely together, and ren- 

 ders it necessary for the female to make greater effort 

 and to have recourse to special expedients in order to 

 free herself from the roe. It is said'' that in the spawn- 

 ing-season the female rubs her belly against a sharp 

 stone or a piece of ^vood, until she succeeds in fastening 



out by fact. It is during the spawning-season that the 

 difference of sex first becomes apparent in the brighter 

 and more vivid colouring of the male and the deeper 

 shape of the female, which is perhaps always visible at 

 this season'. 



The courage \\ith which it defends itself, and the 

 fornndable weapons against fishes of prey which it pos- 

 sesses in its sjiinous tins, tend to preserve the Perch 



the roe-string to this object, whatever it may be. She \ from attack as soon as it has reached an age when it 



then darts suddenly forward with a winding motion, 

 and thus draws out the roe in the form of a string 

 which in some way resembles the strings of spawn Avhich 

 certain batrachians deposit. Now and again, however, 

 the roe is found lying loose on some water-plant' or 

 drifting about in the water''. The eggs are numerous, 



can defend itself. It swims rapidly, but not continuously. 

 After each dart forwards it sto]is for a moment. It 

 generally keeps close to the bottom, and sometimes 

 half-way bet^veen the bottom and the sui-face. It is 

 only on bright and calm summer days that it disports 

 itself at the surface. About midsummer comes the time 



In the t)eginning of Dec, 1880, among females with eggs about 1 mm. in size, we have found 



tlic weight of specimens 266 mm. long to be 281 grm., the weight of specimens 288 mm. long to be 361 grm., 

 , 278 3 » » » 276 ) s . ' 305 » » » » 361 » 



281 -> -> ■> > 332 > > ■ > 330 ^ » » » 553 > 



" XORBACK (Fiskevdrd ocli Fiskafvel, p. 359) and Maklix (1. c.) state that the Perch is capable of propagating itself when two years 

 old. That tliis holds good in the case of the males, is undoubtedly true, at least if the estimate of age given above be correct, for in Lilla 

 Vartau (a firth of the Baltic near Stockliolm) on 12th of May, 1887, males 127 mm. in length (measured to the end of the middle rays in the caudal 

 fin) were found to have fluid milt. The smallest female ready to deposit its spawTi, which was caught on the same occasion, measured 154 mm. in length. 

 '' LVND, Vet.-Akad. Handt. 1761, p. 188. 

 '■ Malm, Gbgs, Uoh. Fit., p. 377. 

 "* Su.NDEVALL, Vet.-iMcad. Handl. 1855, p. 9. 

 ' Natarg. Fische Deittschl., 2 Th., p. 68. 



/ The truth of this statement is most clearly shown by the fact that in the case of 3 malts and 4 females the least depth of the body, or the 

 least depth of the tail was more than 30 •'„ of the greatest depth of the body, while in the females it was less than 30 •.. 



