404 ANGUILLIDJE. 



extends to below the posterior border of the eye, specimens occur in which it reaches 

 a little further back, whilst in others it falls below the centre of the eye. Gunther 

 has given as the chief distinctive character of A. latirostris the shorter interspace 

 between the origin of the dorsal fin and that of the anal, which in A. vulgaris usually 

 equals or a little exceeds the distance between the end of the snout and the gill- 

 opening; and he points out that a figure (pi. cxcii.) of an Egyptian Eel in Bifaud's 

 work presents this character. I doubt whether reliance can be placed on the rendering 

 of such details in any of Rifaud's figures, and surely I have never seen an example of 

 Anguilla vulgaris with the two fins originating so near each other ; but an inspection 

 of the annexed table of measurements will show that no great importance can be 

 attached to the character as defined by Gunther. In an example from England 

 (Itchen), the first of A. latirostris mentioned in Giinther's Catalogue, the distance 

 between the origin of the two vertical fins is 67 millimetres, whilst the length of the 

 " head " to the gill-opening is 82. 



Anguilla vulgaris is a catadromous fish, compelled to return to the sea at the time of 

 reproduction, which takes place at great depths in the Mediterranean and the North 

 Atlantic. Only barren specimens remain throughout their life in fresh water, where 

 they may grow to an enormous size. The fish is said to die after breeding; at any 

 rate it does not re-enter fresh waters. The larval form has been described as 

 Leptocephalus brevirostris, Kaup ; it transforms into what is called the " Elver," similar 

 in general, form to the adult but semi-transparent, scaleless, and measuring from 50 to 

 75 millimetres in length. The minute scales only appear much later, when the fish is 

 about 200 millimetres long *. 



The Elvers ascend rivers in countless myriads, but I am not aware that anything 

 has been recorded of the phenomenon in Egypt or of the season at which it takes 

 place. The smallest Egyptian Eel I have seen is 70 millimetres long, and was obtained 

 at Ghet-el-Nassara on June 10th, 1899. 



The following is a list of the Egyptian and Nubian specimens examined : — 



1 Mediterranean Coast of Egypt. — Petherick, 1861. 



1 Lake Borollos. — Loat, 6.11.99. 



6 Lake Menzaleh.— Loat, 16.5.99, 8.6.99. 



59 Freshwater pool near Grhet-el-Nassara, L. Menzaleh. — Loat, 10-11.6.99. 



* The Eel question embraces an enormous literature. The following publications are specially recom- 

 mended :— L. Jacoby, 'Die Aalfrage' (Berlin, 1880), translated in Bep. U.S. Pish Comm. 1882, p. 463.— 

 H. C. Williamson, " On the Beproduction of the Eel," Bep. Eishery Board Scotl. xii. pt. 3, 1894, p. 192.— 

 O. G. J. Petersen, "Tbe Common Eel," Bep. Dan. Biol. Stat. v. 1896.— G. B. Gbassi, " The Beproduction 

 and Metamorphosis of the Common Eel," P. B. Soc. Ix. 1896, p. 260, and Q. J. Micr. Sci. xxxix. 1896, 

 p. 371.— C. H. Eigenmann, "The Solution of the Eel Question," Tr. Amer. Micr. Soc. xxiv. 1902, p. 5.— 

 J, Schmidt, " Life History of Young Eel," Med. Kom. Havundersog. S. Eisk. i. 1905, no. 5. 



