42 PUELIMINAUY NOTES ON THE KErUODUCTION OF TELEOSTEAN 



Artificially fertilized eggs measured from "915 to '955 mm. ; the siugle 

 oil-globule 15 to "16 mm. The oil-globule was colourless, but dark and 

 smoky. 



Tow-net eggs, which can be identified with this species without any 

 risk of error, measure from "97 to '99, the oil-globule from "lo to 

 •165 mm. ; and it may be noted that the oil-globule is usually, but not 

 invariably, of a bright yellow colour — a matter of no real specific 

 importance. Including all tow-net eggs, which seem to me to belong 

 to this species, the diameter varies from "93 to I'Ol mm. 



The zona presents no features of interest, the surface corrugations 

 observable in the newly-extruded ova disappearing as development 

 proceeds. 



Black pigment, as stated by Cunningham, appears before the out- 

 growth of a free tail. At the stage when that organ manifests itself 

 as a short prominence I find that faint black chromatophores are present 

 along the head and trunk, but chiefly on either side of the middle line. 

 At the posterior end they extend on to the yolk sac, forming a small 

 marginal group outlining the end of the trunk. The oil-globule at this 

 stage is postero-ventral. 



Before the tail has attained any considerable length yellow chroma- 

 tophores appear along the sides of the embryo, and a few of each colour 

 associate themselves with the oil-globule, which has (usually) become 

 posterior in position. The chromatophores are very frequently on the 

 hinder face of the globule. The skin shows a tendency to become 

 papillate. 



By the time the tail is of equal length with the trunk large black and 

 yellow chromatophores extend along the sides of the latter, upon the 

 rectal region, and rather irregularly along the tail, showing a tendency 

 to form a posterior pigment bar. In all specimens which I have seen 

 the epidermis is by this time more or less distinctly papillate, especially 

 on the yolk sac. The papillae are ovoidal, and not connected with each 

 other by apparent ridges or stride. Usually they are extremely con- 

 spicuous, and as characteristic of the species as such variable structures 

 ever are in Teleostean embryos. 



The newly-hatched larva measures, in one instance, 2'09 mm. The 

 hind end of the yolk is I'oS mm. from the snout, and '25 in front of the 

 anus, which is thus considerably posterior to median. The wide inter- 

 space between yolk and anus is characteristic of all larvic which I have 

 seen, but there are minor differences of dimension. Thus another 

 specimen, soon after hatching, is 2*85 mm. long, and there is a space 

 of •44 mm. between yolk and anus. In some cases the yolk is ovoidal, 

 and extends in front of the snout, but usually it appears to be more 

 oblong in profile. The oil-globule is normally posterior, but may be 



