194, NORTH SEA INVESTIGATIONS. 
about 1:03 to 1:09 mm. in diameter before fertilization ; it possesses 
a single oil-globule, °26 to ‘'27 mm., either colourless or of a bright 
orange colour (and probably of any intermediate tint), which presum- 
ably disappears more or less with the development of the egg. 
The perivitelline space is probably small. The yolk is colourless, and 
segmented throughout, the segments in early stages having a very 
characteristic vesicular appearance, not noticeable in the ova of 
Clupeoids. 
So far as I am aware, no other acanthopterous fish is known to 
possess an eg’ with completely segmented yolk. The existence of 
this feature in such widely separated families as the Clupeidee and 
Carangidz seems to show that it is of no taxonomic importance. 
VII. On a Dwarr Variery oF THE Praice (Pleuronectes platessa, 
Lryn.), witH some REMARKS ON THE OCCASIONAL CILIATION OF 
THE SCALES IN THAT SPECIES. 
On the 28th February, 1894, I noticed a number of boxes of small 
plaice in the Grimsby market, and was informed that they had been 
consigned thither by cargo steamer from Hamburg. 
It was at once apparent that they differed in some respects from 
the small plaice landed by our own fishing- boats, as also from any 
that I had hitherto examined among consignments which reach this 
port from time to time from Continental sources. It was evident, 
in fact, that, although very small, they were nearly all sexually 
mature, and actually ripe. 
I selected what appeared to be a representative series for closer 
examination at the Cleethorpes Laboratory, and found that the 
smallest ripe female measured only 94 inches in total length, whilst 
the largest fish of the lot, also a ripe female, was only 134 inches 
long. My selection, having been made mainly with a view to inquiry 
as to size in relation to sexual maturity in the more important sex, 
consisted almost entirely of females. 
With the exception of the coloration, which was in some indi- 
viduals rather unusual, I could detect no character in which these 
fish differed to an appreciable extent from the North Sea examples 
with which I am familiar, but from the presence in the same consign- 
ment of a number of unusually spinous flounders (P. flesus, Gottsche) 
I formed the idea that they must have been caught in some locality 
to which our own vessels never penetrate. 
I need hardly say that, in view of the opinion I have expressed in 
this Journal and elsewhere as to the large size at which North Sea 
plaice first begin to spawn, the occurrence of such small mature exam- 
ples (possibly from a North Sea ground) came as rather a shock to me. 
