Miscellaneous. 65 



far enough to form the mouth, but certainly not sufficient!}' to form 

 the mentum. Still later, and also upon the back, the cloaca will 

 be formed by an invagination of the ectoderm ; and this, although 

 very long in the adult, is still very short in the larva, and remains 

 reduced to a simple emargination in the Floscularke. The cephalic 

 region is soon bounded by a slight fold, which indicates the margin 

 of the chitinous covering. The eyes make their appearance as two 

 red points ; cilia begin to move, at first upon the infrabuccal pit, 

 then upon the mouth, and finally upon the top of the head, where 

 they form a sort of circlet. The armature of the mastas is formed, 

 the tail withdraws by degrees towards the extremity of the e^^, the 

 envelope of which it finally ruptures. It has already been described 

 by several authors ; and I shall dwell only upon this fact, that, like 

 the larva of Lacimdaria figured by Huxley, it presents cilia upon 

 three points of the body — a continuous and scarcely sinuous circlet 

 placed above the mouth, a second circle surrounding this circlet and 

 the mouth, and extending even over the vibratile pit, and, lastly, a 

 tuft of cilia at the extremity of the tail. The larva remains active 

 for several hours, and then attaches itself by means of the glands 

 contained in its tail. It is then that it begins to collect in the 

 vibratile pit the minute particles suspended in the water. These it 

 mixes with the secretion from a gland, hitherto taken for a ganglion, 

 and, according to the judicious observations of Gosse and Williamson, 

 forms of them those little balls which, when juxtaposed, constitute 

 the tube that it inhabits. — Comptes Rendm, November 21, 1881, 

 p. 85G. 



On a Yellow Varieft/ of the Common Ed (Anguilla vulgaris, FL). 

 By Dr. Heixrich Bol.vx, of Hamburg. 



On the 2nd July, 1879, a very interesting, pure sulphur-yellow 

 variety of our river-eel, which had been taken in the Elbe near 

 Hamburg, was brought to me for the aquarium of our Zoological 

 Garden here. This first example was followed by thirteen other 

 similar ones in the interval between the 4th September and the 9th 

 October of the same year. In the summer of the present year 

 (1880) the occurrence of the yellow eels in the Elbe was repeated. 

 On the 5th '^hxy I received two specimens, and then gradually, up 

 to the 13th August, seven others. 



Only the eel first captured, which is still living in the aquarium, 

 is pure yellow without black spots. It is about 32 ccntim. 

 (13 inches) long. Its upper surface and sides are of a beautiful 

 light lemon-yellow ; the muzzle is rather more orange-coloured. In 

 the hinder half of the body, and especially the tail, there are on the 

 sides numerous whitish spots in the yellow. The whole underside 

 is whitish and shining, while the yellow parts of the body are dull. 

 The fins are pale yellow and so translucent that the finer blood- 

 vessels may be detected in them with the naked eye ; in the same 

 way the blood shows reddish through the skin on the whitish lower 



Ann. & Mag. N. lUst. Ser. 5. Vol ix. 5 



