— i69 — 



The height of the body at the centre is now also considerably less than before, and 

 the thickness has greatly increased, so that towards the close of this stage (4 B) the 

 body becomes nearly cylindrical (PI. VIII, Fig. 10). There is still a narrow strip remaining 

 of the clear, transparent zone between the interspinous region and the contour of the 

 body proper. 



The distance from the beginning of the anal fin to the end of the tail was ca. 59 % 

 of the total length in the two specimens to hand and was thus no greater than in the 

 previous stage. On the other hand the anterior point of the dorsal fin has moved con- 

 siderably far forward. A fairly large amount of pigment is present on the end of the 

 tail, both internally and on the surface of the fin itself. The neck on the other hand is 

 still quite free of pigment. 



5th Stage PI. VIII, Fig. U-12 



(Place and time of occurrence: nearer to the coasts of West and North Europe and 

 in shallower water than the previous stages : from November to May or even later. Several 

 thousands specimens examined). 



In this stage, which is almost identical with Grassi and Calandruccio's "hemilarve", 

 the French fishermen's "civelle" or "pibale" and the Spanish fishermen's "angula", the height 

 of the body is a good deal less than in the previous stage, as also the thickness of the 

 body, which is considerably less than in Stage 4. The body is however still higher 

 (more compressed) than in Stage 6. In contrast to Stage 4 the transparent zone between 

 the interspinous regions and the contour of the body is now quite lacking. The distance 

 from the beginning of the anal fin to the end of the tail varied (in 4 specimens) between 

 ca. 61 and 63% af the total length and is thus not much if anything greater than in 

 Stage 4. The pigment of the tail is essentially as in the previous stage, sometimes more 

 pronounced, sometimes a little weaker. Superficial pigments begins to appear at this 

 stage ( see Fig. 6) on the neck, but the body apart from the tail is free of pigment. The 

 specimens with superficial neck pigment I designate as being at Stage 5 B to distinguish 

 them from those which lack this pigment and may be said to be at Stage 5 A. How far 

 the development of the pigment agrees however with the other inner and outer develop- 

 ment I do not know. 



At the end of this stage weak pigment appears over the whole of the dorsal aspect 

 and we are thus led on to the 6 Stage, the last in the metamorphosis. 



6th Stage PL VIII, Fig. 13 



(Place and time of occurrence: coasts of North and West Europe in shallow as also 

 fresh water in the spring and summer months). 



This stage is the last in the metamorphosis and the one which immediately precedes 

 the period, when the small eels begin to feed and thus to grow, after the considerable 



morphosis of a specimen of a Lepiocephalus breviroslris with larval teeth, state that it was kept in the 

 aquarium for about 40 days and then killed (for preservation) at a little more advanced stage than the 3 

 semiiarvae mentioned from the end of 1892 ("Da un Leptocefalo brevirostre coi denti larvali (tutti?) che 

 visse circa quaranta giorni in un acquario abbiamo ottenuto lo stadio che qui accenniamo (I'individuo venne 

 ucciso e conservato), ritenendolo di poco piii avanzato delle tre semilarve or ora accennate", Grassi & Calan- 

 DRUCCIO, I. c. p. 12 — 13). How these statements, that the specimen shown in Fig. 4 (therefore at my Stage 4) 

 was killed and preserved at a little more (poco più) advanced stage than the three semiiarvae which however 

 became completely metamorphosed and began to feed and grow, can be brought into agreement I cannot 

 understand nor does it appear possible from the statements of the Italian authors. 



