THE EEL FAMILY. 437 



or 8 cm. ' At this period they take on the yellowish brown 

 tinge of the adult. From the length of 9 cm. and better, 10 or 

 11cm., they retain the preceding colour. They are then opaque, 

 being with difificulty examined by transmitted light, and have, 

 except for their length, the external appearance of the adult. 

 These peculiarities are still more marked in individuals of the 

 length of 12, 13, or 14 cm. According to Valenciennes it is at 

 this period (April or May), three or four months after hatching, 

 that they receive the name civelle. At this period, according 

 to this author, they may be of a beautiful sulphur yellow 

 colour.' Small eels 2|in. long occur between tide-marks in 

 Lochmaddy, North Uist, even so late as August. 



' The development of the eel from the civelle to the adult is 

 regular — without metamorphosis, without the replacement of 

 foetal organs, which disappear, by others which replace them 

 permanently.' 



We thus notice that at the earliest age when the eel is 

 known to us, both the larval and post-larval stages have been 

 reached and passed, and it is only the young eel which comes 

 under our cognisance through its migratory instinct. 



The time at which the mont^e (schools of elvers) is said to 

 appear, varies very much in different countries, and even in 

 different parts of the same country. Robin says that, in the 

 Landes, and no doubt other places in the south, the ascent of 

 the young fishes takes place as early as the second half of 

 December, instead of in March as in the Channel. 



' Observations made on the Orne show that the sea exercises 

 a sensible influence on the arrival of the little eel. The fishing 

 is especially fruitful during the two days which precede, and 

 the three days which follow, either the new or full moon. The 

 fry, unable to stem the current, take advantage of the spring- 

 tides to enter the rivers.' 



The young eels on entering a river swim eagerly up stream. 

 Numbers leave the main body and follow the course of each 

 tributary. They overcome obstacles in a remarkable manner, 

 ascending even perpendicular rocks by creeping through the 

 algce or wet moss covering the stones. They burrow readily 

 into the soft mud. The ascent of the young eels has been 



