FOOD OF POST-LARVAL FISH. 443 
LEPADOGASTER GOUANI Lacep. 
Five specimens from outside the Breakwater, Aueust and October, 
4 to 6 mm. The largest contained 1 Centropages typicus and 2 
Pseudocalanus elongatus, 2 contained nothing, and the others Copepod 
nauplii and Harpacticids. 
RHAMPHISTOMA BELONE (L.). GaAr-FIsH. 
Sixteen specimens from both within and without the Breakwater, 
July and August, from amongst Zostera, 10 to 29mm., 6 contained 
nothing, 6 contained Harpacticus uniremis, the rest greenish food remains 
and 1 Plewrosigma sp. 
PLEURONECTID. 
Very few Pleuronectids were obtained fresh from the tow-nettings, 
but a large number from the Young Fish Trawl, 1914, were examined in 
a preserved state for food and show some interesting features. Thus we 
find they fall into two groups according to the form of the alimentary 
canal, which influences the food taken in the young forms. In the first 
eroup we may place those with a large mouth and a thick and short 
gullet and stomach ; to this group belong Solea variegata, S. vulgaris, 
S. lascaris, Pleuronectes limanda, Rhombus maximus, R. levis, Zeugo- 
pterus punctatus, Z. unimaculatus and Scophthalmus norvegicus. With this 
character goes the habit of taking such food as small Copepods and 
Cladocera at an early stage, so that the newly hatched fish very soon, and 
in some cases almost immediately, takes this food. The Plaice Pleuronectes 
platessa would probably be included in this group although in the very 
first stages after hatching it is known to eat diatoms and larval mol- 
lusks, soon however taking to Copepods and other small Crustacea, 
especially Entomostraca. The nearest to the Plaice in this respect is the 
Dab, P. limanda, which seems not to begin to eat Copepods until about 
5 mm. in length, although it hatches under 3mm. On the other hand 
Solea variegata hatches at about 2-5 mm. and at 4mm. it may contain 
a fairly large Temora measuring 15mm. Scophthalmus norvegicus 
hatches at about 2-5 mm. and still has yolk at 3-27 mm., but at 4-5 mm. 
it can eat a Metridia 2 mm. long. In these cases Copepods must be eaten 
very soon after hatching. 
In the second group we may include Pleuronectes flesus, P. micro- 
cephalus and Arnoglossus laterna which have a long and narrow gullet 
and stomach, and these apparently do not eat Copepods or any Crustacea 
until a greater size is reached—the alimentary canal in the small speci- 
mens being either empty or showing indications oi a diet of unicellular 
