HECENT KEPORTS OF FISHERY AUTIIOHITIES. 379 



the eye had a diameter, both vertical and transversal, of 9 mm. ; and 

 in another eel of 33^ cm. the same measurement was recorded. In a 

 female eel, derived from the same source and purchased in the market, 

 whose length was 48i cm., the vertical diameter of the eye was 10 mm., 

 and the transversal diameter rather more than 10 mm. These are not 

 the greatest dimensions which I observed, and I conclude from these 

 facts that the bridal-habit described by Petersen was not quite 

 completed in his specimens, and that it becomes so only in the sea and 

 at a great depth. In relation to these observations of mine stands the 

 fact that the genital organs in the eel taken in the Messina currents 

 are sometimes more developed than in eels which have not yet entered 

 the deep water. Thus it has happened that male individuals have 

 occurred, showing in the testes here and there knots of spermatozoa. 

 These spermatozoa are similar to those of the Conger vulgaris, and must 

 be considered as ripe. As is well known, so advanced a stage of sexual 

 maturity has never before been observed in the common eel. This 

 appears to be due to the fact that the males hitherto examined had not 



yet migrated into the deep water of the sea 



" To sum up, Anguilla vulgaris, the common eel, matures in the 

 depths of the sea, where it acquires larger eyes than are ever observed 

 in individuals which have not yet migrated to deep water, with the 

 exception of the eels of the Eoman cloacie. The abysses of the sea are 

 the spawning places of the common eel : its eggs float in the sea water. 

 In developing from the egg, it undergoes a metamorphosis, that is 

 to say, passes through a larval form denominated Leptoccphalus 

 brcvirostris. What length of time this development requires is very 

 diilicult to establish. So far we have only the following data : — Inrst, 

 Anguilla vulgaris migrates to the sea from the month of October to the 

 month of January; second, the currents, such as those of Messina, 

 throw up from the abysses of the sea specimens which, from the 

 commencement of November to the end of July, are observed to be 

 more advanced in development than at other times, but not yet arrived 

 at total maturity ; third, eggs, which according to every probability 

 belong to the common eel, are found in the sea from the month of 

 August to that of January inclusive ; fourth, the Lq)tocc2)halus 

 brcvirostris abounds from February to September. As to the other 

 months, we are in some uncertainty, because during them our only 

 natural lisherman, the OrUiagoriscus mala, appears very rarely ; lifth, 

 I am inclined to believe that the elvers ascending our rivers are already 

 one year old, and I have observed that in an aquarium specimens of 

 L. brcvirostris can transform themselves into young elvers iu one 

 month's time." 



NEW SERIES. — VOL. IV. NO. 4. ^ D 



