of the Fishery Board for Scotland. 315 
Acartia Clausii, Giesbrecht.—All the specimens: of Acartia observed 
belonged to the one species, viz., A. Clausi’. This is quite a distinct form, 
especially as regards the structure and armature of the fifth feet, and in 
this respect it differs very markedly from Acartia longiremis, Lilljeborg. 
So far as known, the distribution of Acartia Clausii appears to be even 
more extensive than, though probably not so general as, Centropages 
typicus. ‘The area of its known distribution includes the Mediterranean 
(Giesbrecht, Claus, Gourret, I. C. Thompson), Libreville, Gaboon River, 
West Africa (Mihi), Canary Islands (I. C. Thompson, Wimereux (Canu), 
Plymouth (Bourne), Loch Fyne, Scotland (Norman), Firth of Forth, 
Scotland (Mihi). The present seems to be one of the most northerly 
records hitherto reported for this species. 
Ozthona (?) semilis, Claus.—All the ‘ Research’ specimens of Ozthona 
appear to belong to the species described by Dr Giesbrecht as Ozthona 
similis, Claus. Dr Giesbrecht seems to consider that most of the British 
records of Ozthona spinifrons are referable to this species, and he is _ 
satisfied that Ozthona spinirostris, Giesbrecht, is also identical with it. 
The authentic distribution of Ovzthona similis is limited to a compara- 
tively few places ; as, for example, Nice, Trieste, and Gulf of Naples in 
the Mediterranean (Claus, Car, Giesbrecht), Kieler Fohrde (Giesbrecht), 
Bay of Wismar, Baltic (Braun), West Baltic (Hensen), the Indian and 
Pacific Oceans (Giesbrecht). 
Lictinosoma atlantica (Brady and Robertson).—This minute species 
has to all appearance a world-wide distribution. Besides the various 
records of its occurrence around the British Islands, it has also been 
reported from the North and South Atlantic and the Pacific Oceans 
(the Gulf of Guinea, West Coast of Africa, near Ascension Island ; and 
near the Galapagos Island). Hetinosoma atlantica is so minute that it 
has doubtless often escaped observation : it is sometimes a moderately 
common species in Loch Fyne. 
Podon intermedius, Lilljeborg.—All the specimens of Podon observed 
belonged to this species, which is readily distinguished from P. poly- 
phemoides by the number of hairs of the second antenna—one branch 
having seven and the other six hairs. 
Parathemisto (1) gracilipes, Norman.—None of the specimens of 
Parathemisto obtained appeared to be mature, but, as far as could be made 
out, they all belonged to P. gracilipes, which is a smaller species than 
P, oblivia. 
